Friday, December 31, 2010

Thursday, December 30, 2010

ERNET India Recruitment

ERNET India
Electronics Niketan, 6, CGO Complex, Lodhi Road, New Delhi - 110003

ERNET India is looking for suitable personnel for filling up of the following posts of System Administrators on contract basis :

  • System Administrator : 09 posts (UR-5, SC-2,OBC-2), Age : 27 years, Remuneration : Rs. 27000/- per month

Application Fee : Deposit Rs.500/- in Bank of India A/c No. 604810100002033 of ERNET India. SC/ST candidates are exempted from fee.

How to Apply : Apply Online upto 21/01/2011 at ERNET India website only :

Please view http://www.eis.ernet.in/tenderdocs/20101226sa.pdf for more details and apply Online at http://202.41.97.89/sysadmin/

The Kerala Minerals And Metals Limited Recruitment

The Kerala Minerals And Metals Limited (KMML)
(A Government of Kerala Undertaking)
Sankaramangalam,Chavara, Kollam, Kerala, India -691583 (by sarkari-naukri.blogspot.com)

KMML requires various personnels in the projects on Permanent as well as on contract basis :
  1. Operator Grade B : 02 Posts
  2. Junior Operator : 05 Posts
  3. Junior Operator : 14 Posts on contract basis
  4. Junior Safety Inspector : 01 Post

How to Apply : Typewritten application giving complete resume with recent photograph, enclosing self attested copies of all relevant certificate should reach to The Joint General Manager (P&A/EDP), The Kerala Minerals and Metals Ltd, PB No.4, Sankaramangalam, Chavara PO, Kollam – 691583upto 05/01/2011.


Please view http://kmml.com/uploaded_files/ads_promos/ads_29.pdf for further details and application format.

KIOCL Limited Recruitment

KIOCL Limited (Formerly Kudremukh Iron Ore Company Limited)
(A Government of India Undertaking)
Regd.Office: II Block, Koramangala, Bangalore-560034.

KIOCL Invites applications for the following posts for its establishment and its subsidiary unit:

  • Graduate Engineer Trainees : 32 posts (UR-12, OBC-13, SC-4,ST-3), Scale of pay : Rs.8600-250-14600/-(E0) , Qualification :First Class Engineering degree in Mechanical/ Electrical & Electronics/ Civil/ Electronics & Communication/ Computer Science/ Mining discipline (Second Class for SC/ST candidates), Age : 27 years as on 31/12/2010.

How to Apply : Application in the prescribed format may be sent on or before 20/01/2011 to :

Senior Manager (Personnel), KIOCL Limited, II Block, Koramangala, Bangalore - 560034

For further information and application format, kindly view http://www.kioclltd.com/openings/GET-2010.pdf

Hindustan Aeronautics Limited Recruitment

Hindustan Aeronautics Limited (HAL)
Aircraft Division, Nashik
HAL Aircraft Division, Nasik is Hyderabad invites application for the following posts :
  1. Assistant Engineer (Mechanical) : 14 posts (ST-9, PH-5), Age : 28 years, Pay Scale : Rs.12600-3%-32500
  2. Deputy Manager (Human Resources) - Legal : 01 post, Age : 45 years, Pay Scale : Rs.20600-3%-46500
  3. Medical Superintendent / Senior Medical Officer (Medicine) : 01 post, Pay Scale : Rs. 24900-50500 / 20600-46500
  4. Team Leader (Waranty Cell) : 05 posts, Age : 45 years, Pay : Consolidated amount.

How to Apply : Eligible candidates may send their duly filled in applications in the prescribed format so as to reach on or before 20/01/2011 to Deputy General Manager (Human Resources), Post Box No. 23, Ojhar Township Post Office, Nashik - 422207. The envelope should be superscribed with the title of the post applied for.

Please visit http://emodeapply.com/hal-nasik/ for complete details and application format.

Sunday, December 19, 2010

UPSC ENGINEERING SERVICES - CIVIL ENGINEERING QUESTIONS

1. The live load for a sloping roof with slope 15°, where access is not provided to the roof,
is taken as
A 0.65 kN/rn2
B. 0.75 kN/ rn2
C. 1.35 kN/ rn2
D. 1.50 kN/ rn2

Answer: (A)

2. The batten plates used to connect the components of a built-up-column are designed to resist
A Longitudinal shear only
B. Transverse shear only
C. Longitudinal shear and moment arising from transverse shear
D. Vertical shear only

Answer: (C)

3.The duration of any activity in case of a PERT programme is calculated as a weighted average of three time estimates namely the optimistic time to , the pessimistic time tp and the most probable time tm which is given as

Answer: (B)

4. In ISMC 400 channels placed back to backat a spacing of 26 cm carry an axial load of
160 tonnes. The lacing system should be designed to resist a transverse shear of
A 16 tonnes
B. 12 tonnes
C. 8 tonnes
D. 4 tonnes

Answer: (D)

5. Consider the following statements of network:
1. Only one time estimate is required for each activity.
2. Three time estimates for each activity.
3. Time and cost are both controlling factors.
4. It is build-up of event-oriented diagram.
Which of the above statements are correctly applicable to CPM network?
A 1 and 3
B. 1 and 2
C. 2 and 4
D 3 and 4

Answer: (A)

6. If a simply supported concrete beam, prestressed with a force of 2500 kN, is designed by load balancing concept for an effective span of 10 m and to carry a total load of 40 kN/m, the central dip of the cable profile should be
A 100mm
B. 200 mm
C. 300mm
D. 400 mm

Answer: (B)

7. A circular shaft which has a diameter of 100 mm is subjected to a torque of 5 kN-m. The shear stress, in N/mm2 , induced in the shaft would be

A160/Π
B.120/Π
C.125/Π
D.80/Π

Answer: (D)

8. Match List I with List II and select the correct answer using the code given below the lists:
List I
(Type)
A. Single angle in roof trusses
B. Double angles in roof trusses
C. Single I section in columns
D. Double I section in columns

List II
(Recommended
Slenderness ratio)
1. 80 — 150
2. 30—60
3. 100- 180
4. 60 — 120

Codes

A B C D
A 3 4 1 2
B. 2 4 1 3
C. 3 1 4 2
D.2 1 4 3

Answer: (B)
9.

Answer: (D)

10. Consider the following statements relating to structural analysis
1. Flexibility matrix and its transpose are equal.
2. Elements of main diagonal of stiffness matrix are always positive.
3. For unstable structures, coefficient in leading diagonal matrix can be negative.
Which of the above statements is/are correct?
A 1, 2 and 3
B. 1 and 2 only
C. 2 and 3 Only
D. 3 only

Answer: (B)

11.

Answer: (A)

12. Poisson’s ratio is defined as the ratio of
A Longitudinal stress and longitudinal strain
B. Lateral strain and longitudinal strain
C. Longitudinal stress and lateral stress
D. Lateral stress and longitudinal stress

Answer: (B)

13. Consider the following conditions with respect to plastic analysis :‘
1. Sum of internal and external forces and moments must be equal to zero.
2. At ultimate collapse load, the number of plastic hinges must be just enough to form a mechanism.
Which of the above conditions is/are correct?
A 1 only
B. 2 only
C. Neither 1 nor 2
D. Both land2

Answer: (D)

14. The base plate of a roof truss is attached to the concrete pier with the help of 16 mm diameter mild steel anchor bolts of grade fy = 250 MPa. What is the maximum pull the base can be subjected to, if the root area of bolt = 0.75 times shank area ?
A 30 kN
B. 67.5 kN
C. 90 kN
D. 120 kN

Answer: (A)

15. The maximum longitudinal pitch allowed in
bolted joints of tension members is
A 16 times the diameter of the bolt
B. 32 times the diameter of the bolt
C..16 times the thickness of the plate
D. 32 times the thickness of the plate

Answer: (C)

16. A father notes that when his teenage daughter uses the telephone she takes no loss than 5 minutes for a call but sometimes as much as an hour. 15 minutes calls are more frequent than calls of any other duration. If the daughter’s calls were to be represented as an activity in PERT project, the expected duration of each phone call is?

A 89/6 minutes
B. 101/6 minutes
C.113/6 minutes
D.125/6 minutes

Answer: (D)

17

Answer: (B)

18.A propped cantilever of span L is subjected to a concentrated load at mid span. If Mp, is
the plastic moment capacity of the beam, the value of collapse load will be

A. 12Mp/L
B. 8Mp/L
C 6Mp/L
D. 4Mp/L

Answer: (C)

19. In PERT analysis, the time estimate of
activities correspond to
A Normal distribution
B. Poisson’s distribution
C.β distribution
D. Binomial distribution

Answer: (C)

20. Consider the following statements:
1. Shape factor
2. Length of the beam
3. Type of loading
4. Yield strength of material
Which of these affect the influence length of
plastic hinge in a beam?
A. 1 only .
B. 1 and 3
C. 2 and 3
D. 3 and 4

Answer: (B)

21

Answer: (A)

22. Consider the following statements:
1. PERT is activity-oriented and adopts deterministic approach.
2. CPM is event-oriented and adopts probabilistic approach.
3. PERT is event-oriented and adopts probabilistic approach.
Which of the above statements is/are correct?
A 1 only
B. 1 and 2
C. 2 and 3
D. 3 only

Answer: (D)

23

Answer: (D)

24.PERT calculator yield a project length of 60 weeks with a variance of 9 weeks. Probability factor, corresponding to 95% probability is 1.647; then the number of weeks required to complete, and project with a probability of 95% is,
A 60.94
B. 62.94
C. 64.94
D. 66.94

Answer: (C)

25. For an I-beam, the shape factor is 1.12; the factor of safety in bending stress is 1.5. If the allowable stress is increased by 20% for wind or ,earthquake loads, then the load factor is
A 1.10
B. 1.25
C. 1.35
D 1.40

Answer: (D)

26. A steel plate is 300 mm wide and 10 mm thick. A rivet of nominal diameter 18 mm is driven. The net sectional area of the plate is
A 1800 mm2 .
B. 2805 mm2
C. 2820 mm2
D 3242 mm2

Answer: (B)

27. At a section along the span of a welded plate girder, in which the web is spliced, the bending moment, at a section is M. The girder is comprised of top flange; web and bottom flange plates all of equal areas. The share of the bending moment taken by splice plates would be
A M
B. M/L
C. M/7
D M/13

Answer: (C)

28. Consider the following stipulations in designing a laced column
1. Single lacing systems on opposite planes shall preferably be in the same direction so that one is the shadow of the other.
2. Lacing bar should be a flat section.
3. The slenderness ratio of the lacing bars for compression shall not exceed l80.
4. Laced compression members are to be provided with tie plates at ends.
Which of the above observations is/are correct?
A 1 only
B. 1 and 3
C. 2 and 4,
D. 1 and 4

Answer: (D)

29. At the location of a plastic hinge,
A Radius of curvature is infinite
B. Curvature is infinite
C. Moment is infinite
D. Flexible stress is infinite

Answer: (B)

30

Answer: (D)

31. Consider the following statements:
Entrainment of air in concrete is done so as to
1. Increase the workability.
2. Increase the strength.
3. Increase the resistance to freezing and thawing
Which of the above statements is/are correct?
A. 1, 2 and 3
B. 1 only
C. 1 and 3 only
D. 3 only

Answer: (C)

32. Consider the following statements is work breakdown structure
1. It is a graphical representation of entire programme.
2. The Top-Down approach to planning is adopted.
3. The Down-Top approach to planning is adopted.
4. It is suitable for complex projects.
Which of the above statements is/are correct?
A. 1 only
B. 2 and 4
C. 3 and 4
D. 4 only

Answer: (B)

33. If P is the percentage of water required for determination of normal consistency of cement, then percentage of water to be added for determination of initial setting time is
A. 0.70P
B. 0.75 P
C. Q.80 P
D. 0.85 P

Answer: (D)

34. Consider the following statements regarding the. slope of cost-time curve:
1. It is given by difference between normal cost and crash cost divided by crash time.
2. It is given by difference between crash cost and normal cost divided by difference between crash time and normal time.
3. It is given by difference of crash cost and normal cost divided by normal time.
4. It is given by ‘crash cost not divided by crash time.
Which of the above statements is/are correct?
A. 1 only
B.2 and 3
C. 2 only
D. 3 and 4

Answer: (C)

35. Consider the following statements:
1. The crushing strength of concrete is fully governed by water-cement ratio.
2. Vibration has no effect on strength of concrete at high water-cement ratios.
3. Workability of concrete is affected by improper grading of aggregates.
Which of the above statements.is/are correct?
A. 1,2 and 3
B. 2 and 3 only
C. 2 only
D.3 only

Answer: (B)

36. The load carrying capacity of a column designed by working stress method is
500 kN. The ultimate collapse load of the column is
A 500 kN
B. 662.5 kN
C, 750kN
D.1100 kN

Answer: (C)

37. Consider the following statements:
1. Strength of concrete cube is inversely proportional to water-cement ratio.
2. A rich concrete mix gives a higher. strength than a lean concrete mix since it has more cement content.
3. Shrinkage cracks on concrete surface are due to excess water in mix.
Which of the above statements is/are correct?
A 1, 2 and 3
B. 1 and 2 only
C. 2 only
D. 2 and 3 only

Answer: (A)

38. A beam of symmetrical. I-section, made of structural steel has an overall depth. of 300 mm. If the flange stresses developed at the top and bottom of the beam are 1200 kg/cm2 . and 300 kg/cm2 . respectively, then the depth of neutral axis from the top of the beam would be
A 250mm
B.240mm
C. 200 mm
D. 180 mm

Answer: (B)

39. Consider . the following statements:
Admixtures are added to concrete to
1. Increase its strength.
2. Reduce heat of hydration.
3. Delay the setting of cement.
4. Reduce water-cement ratio.
Which of the above statements is/are correct?
A 1 only
B. 1 and 2
C. 2 and 3
D. 3 and 4.

Answer: (B)

40. A building contractor discovers from his record that in the last 200 slab castings his mixer machine broke down 21 times. During each breakdown, he had to pay on an average about Rs. 2,500 for idle labour. A standby mixer machine, if hired on the day of slab casting, would cost him Rs. 200 per day. The expected loss is more than the mitigation expense of hiring the mixer by
A Rs. 151.50
B. Rs. 241.50
C. Rs. 262.50
D. Rs. 283.50

Answer: (?)

41. A steel beam is replaced by a corresponding aluminium beam of same cross-sectional shape and dimensions, and is subjected to same loading. The maximum bending. stress will
A Be unaltered
B. Increase
C. Decrease
D.Vary in proportion to their modulus of elasticity

Answer: (A)

42

The distribution factors for members AE and AC of the box section are
A 0.5 and 0.5
B. 0.6 and 0.4
C. 0.25 and 0.75
D. 1 and zero

Answer: (A)

43

Answer: (D)

44.Consider the following activities:
1. Pouring of concrete
2. Erection of formwork
3. Curing of concrete
4. Removal of formwork
What is the correct sequence on a network of these activities?
A 1—2—3—4
B.2— 1—4—3
C.2—1—3 —4
D.1—3—2—4

Answer: (C)

45. Which one of the following is relevant to Activity on Node (AON)?
A. Dummy activities may be many
B. There will be no dummy activities
C. It is used for quite complex project
D. It is easier to associate with time flow of activities

Answer: (B)

46. Consider the following statements about the
air entraining admixture in concrete:
1. Improve workability
2. Improve durability
3. Reduce segregation during placing
4. Decrease concrete density
Which of the above statements are correct?
A. 1,2,3and4
B. 1 and 2only
C. 2 and 3 only
D. 3 and 4 only.

Answer: (A)

47.

The RC slab, simply supported on all edges as in above figure, is subjected to a total UDL of 12 kN/m2. The maximum shear force! unit length along the edge ‘BC’ is
A 16kN
B. 12kN
C. 8kN
D. 30kN

Answer: (A)

48.

The above figure indicates a project network; the number at each activity represents its normal duration in days. The critical path is along
A 1—2—3—6—7— 8
B. 1—2 —4—5—7 — 8
C. l—2——5—7— 8
D. 1—2—4—6—7 — 8

Answer: (B)

49.

Answer: (C)

50

In the above network, the duration of activities are written along their arrows. The critical path of the activities is along
A 1—2—3—5—7—8
B. 1—2—3—6—7—8 .
C. 1—2—4—5—7—8
D. 1—2—3—4—5—7—8

Answer: (D)





































































































Saturday, December 11, 2010

Electronics Engineering Questions for PSU Recruitment

1. The difference between the number of atoms in a unit cell of a bcc crystal and an fcc crystal is
(a) 1
(b) 2
(c) 4
(d) 6

2. If a small amount of Cu is added to a Ni conductor, then the
(a) resistiviy of Ni will decrease at all temperatures because Cu is a better conductor than Ni
(b) residual resistivity of Ni at low temperatures will increase as Cu atoms act as defect centres
(c) resistivity of Ni will increase at all temperatures as Cu destroys the periodicity of Ni and acts as defects
(d) resistivity of Ni remains unaltered as Cu atoms give the same number of free electrons as Ni atoms

3. For the n-type semiconductor with n = NP and p = ni 2/ND the hole concentration will fall below the intrinsic value because some of the holes
(a) dropback to acceptor impurity states
(b) drop to donor impurity states
(c) virtually leave the crystal
(d) recombine with the electrons

4. Match List I (Magnetic materials) with List II (Dipole arrangement in external field) and select the correct answer using the codes given below the Lists:
List I List II

A. Paramagnetic 1. All dipoles are aligned in one preferred direction
B. Ferromagnetic 2. Half of the dipoles are aligned in opposite
direction and have equal magnitudes.
C. Antiferro-magnetic 3. Half of the dipoles (with equal magnitudes) are
aligned in opposite direction to other half having
equal but lower magnitudes.
D. Ferrimagnetic 4. All dipoles have equal magnitudes but are
randomly oriented.
Codes:
A B C D
(a) 4 3. 2 1
(b) 4 1 2 3
(c) 2 1 4 3
(d) 2 3 4 1

5. For an insulating material, dielectric strength and dielectric loss should be
respectively
(a) high and high
(b) low and high
(c) high and low
(d) low and low

6. Match List I (Optical devices) with List II (Electrical/optical characteristics) and select the correct answer using the codes given below Lists:
List I List II
A. LASER 1. Emits monochromatic light of low intensity
B. Solar Cell 2. Consumes electrical power due to the incident light
C. Photo diode 3. Delivers power to a load
D. LED 4. Emits monochromatic light of high intensity
Codes:
A B C D
(a) 4 3 1 2
(b) 3 4 2 1
(c) 4 3 2 1
(d) 3 4 1 2

7. Which one of the following is the best definition of a superconductor?
(a) It is a material showing perfect conductivity and Meissner effect below a critical temperature
(b) It is a conductor having zero resistance
(c) It is a perfect conductor with highest diamagnetic susceptibility
(d) It is a perfect conductor but becomes resistive when the current density through it exceeds a critical value

8. The ac resistance of a forward-biased p-n junction diode operating at a bias voltage ‘V’ and carrying current ‘I’ is
(a) zero
(b) a constant value independent of V and 1
(c) V/I
(d) delta V/ delta I

9. Match List I with List II and select the correct answer using the codes given
below the Lists:
List I List II
A. Drift current 1. Law of conservation of charge
B. Einstein’s equation 2. Electric field
C. Diffusion current 3. Thermal voltage
D. Continuity equation 4. Concentration gradient
Codes:
A B C D
(a) 2 1 4 3
(b) 4 3 2 1
(c) 4 1 2 3
(d) 2 3 4 1

10. Consider the following statements:
If an electric field is applied to an n-type semiconductor bar, the electrons and
holes move in opposite directions due to their opposite charges. The net current is
1. due to both electrons and holes with electrons as majority carriers.
2. the sum of electron and hole currents.
3, the difference between electron and hole current.
Which of these statements is/are correct?
(a) 1 alone
(b) 1 and 2
(c) 2 alone
(d) 3 alone

11. Consider the following circuit configurations:
1. Common emitter.
2. Common base.
3. Emitter follower
4. Emitter follower using Darlington pair.
The correct sequence in increasing order of the input resistances of these
configurations is
(a) 2, 1, 4, 3
(b) 1, 2, 4, 3
(c) 2,1,3,4
(d) 1,2,3,4

12. Match List I With List II and select the correct answer using the codes given
below the Lists:
List I List II
(Devices) (Property)
A. Silicon diode 1. High frequency applications
B. Germanium diode 2. Very low reverse bias saturation current
C. LED 3. Low forward bias voltage drop
D. PIN diode 4. Cut-off wavelength

Codes:
A B C D
(a) 1 3 4 2
(b) 2 4 3 1
(c) 1 4 3 2
(d) 2 3 4 1

13. The depletion layer across a p+ – n junction lies
(a) mostly in the p+ region
(b) mostly in the n – region
(c) equally in both the p+and n – regions
(d) entirely in the p+ region

14. Match List I (Biasing of the junctions) with List II (Functions) in respect of the BJT and select the correct answer using the codes given below the Lists:
List I List II
A. E-B junction forward bias and C-B 1. Very low gain amplifier
junction reverse bias
B. Both E-B and C-B junctions forward bias 2. Saturation condition
C. E-B junction reverse bias and C-B 3. High gain amplifier
junction forward bias
D. Both E-B and C-B junctions reverse bias 4. Cut-off condition
Codes:
A B C D
(a) 2 3 1 4
(b) 3 2 1 4
(c) 3 2 4 1
(d) 2 3 4 1

15. Match List I (Structures/characteristics) with List II (Reasons) in respect of JFET and select the correct answer, using the codes given below the Lists:
List I List II
A. n-channel JFET is better than p- 1. Reverse bias increases along the
channel JFET channel
B. Channel is wedge shaped 2. High electric field near the drain
and directed towards source
C. Channel is not completely closed at 3. Low leakage current at the gate
pinch-off terminal
D. Input impedance is high 4. Better frequency performance since Mu(n)>> Mu(p)

Code:
A B C D
(a) 4 1 2 3
(b) 4 2 1 3
(c) 3 1 2 4
(d) 3 2 1 4

16. Consider the following statements:
A four-layer PNPN device having two gate leads can be turned on by applying a
1. positive current pulse to the cathode gate.
2. positive current pulse to the anode gate.
3. negative current pulse to the anode gate.
4.’ negative current pulse to the cathode gate.
Which of these statements is/are correct?
(a) 1 alone
(b) 1 and 3
(c) 2 alone
(d) 2 and 4

17. Almost all resistors are made in a monolithic integrated circuit
(a) during the emitter diffusion
(b) while growing the epitaxial layer
(c) during the base diffusion
(di) during the collector diffusion

Directions:
The following items consist of two statements, one labelled the ‘Assertion A’ and the other, labelled the ‘Reason R’ You are to examine these two statements and decide if the ‘Assertion A’and the ‘Reason R’ are individually true and if so, whether the Reason is a correct explanation of the Assertion. Select your answers to these items using the codes given below and mark your Answer Sheet accordingly:
Codes
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is NOT a correct explanation of A
(c) A is true but R is false
(d) A is false but R is true

18. Assertion (A) : BaTiO3 is a piezoelectric material and is used in a record player.
Reason (R) : In a piezoelectric transducer, stress induces polarization and an electric
field strains the material.

19. Assertion (A) : Hall crystal can be used as a multiplier of two signals.
Reason (R) : Hall voltage is proportional to the currents or voltages applied in
perpendicular directions across the Hall crystal.

20. Assertion (A) : The hybrid pi model of a transistor can be reduced to its h-parameter
model and vice-versa.
Reason (R) : Hybrid pi and h-parameter models are inter-related as both of them
describe the same transistor.

21. Assertion (A) : When light falls at the junction of a p-n photo diode, its P side becomespositive and N side becomes negative.
Reason (R) : When a photo diode is short-circuited, the current in the external circuit
flows from the P-side to the N-side.

22. Assertion (A) : Prescalers are used in digital counters to extend the frequency range.
Reason (R) : Prescalers are simple dividing circuits and as such do not have the
high frequency limitation of digital counters.

23. Assertion (A) : CRTs, used in TV receivers are of electrostatic deflection type and
those used in oscilloscopes are of magnetic deflection type.
Reason (R) : TV receivers need a large screen to view pictures, whereas accuracy
is the main consideration in oscilloscopes.

24. Assertion (A) : Alnico is commonly used for electromagnets.
Reason (R) : Alnico has low hysteresis loss.

25. Assertion (A) The solution of Poisson’s equation is the same as the solution of
Laplace’s equation.
Reason (R) : Laplace’s equation is a special case of Poisson’s equation for source-
free regions.

26. Assertion (A) : The fundamental loop of a linear directed graph contains four twigs
and two links corresponding to a given tree.
Reason (R) : Ina linear directed graph, a link forms a closed loop.

27. Assertion (A) : TI ‘zero-state’ response of a linear constant-parameter continuous-
time system can have components having the ‘natural frequencies of the system.

Reason (R) : The ‘forced frequency components in the response of the state for any
given input may not add up to the given zero initial value of the state.
The ‘natural frequency components may be needed to bridge the gap.

28. In a two-terminal network, the open-circuit voltage measured at the given terminals by an electronic voltmeter is 100 V. A short-circuit current measured at the same terminals by an ammeter of negligible resistance is 5 A. If a load resistor of 80 Ohm is connected at the same terminals, then the current in the load resistor will be
(a) 1A
(b) 1.25A
(c) 6A
(d) 6.25A

29 Consider the following statements:
1. Tellegen’s theorem is applicable to any lumped network.
2. The reciprocity theorem is applicable to linear bilateral networks.
3. Thevenin’s theorem is applicable to two-terminal linear active networks.
4. Norton’s theorem is applicable to two-terminal linear active networks.
Which of these statements are correct?
(a) l,2 and 3
(b) 1,2,3 and 4
(c) l,2 and 4
(d) 3 and 4

30. The network has 10 nodes and 17 branches. The number of different node pair voltages would be
(a) 7
(b )9
(c) 10
(d) 45

31. Consider the following statements:
A 3-phase balanced supply system is connected to a 3-phase unbalanced load.
Power supplied to t4is load can be measured using
1. two wattmeters.
2. One wattmeter.
3. three wattmeters.
Which of these statements is/are correct?
(a) 1 and 2
(b) 1 and 3
(c) 2 and 3
(d) 3 alone

32.A capacitor used for power factor correction in single-phase circuit decreases
(a) the power factor
(b) the line current
(c) both the line current and the power factor
(d) the line current and increases power factor

33. Consider the following statements:
If a network has an impedance of (i -j) as a specific frequency, the circuit
would consist of series
1. R and C
2. R and L
3. R,L and C
Which of these statements are correct?
(a) 1 and 2
(b) 1 and 3
(c) 1, 2 and 3
(d) 2 and 3

34. A network contains only independent current sources and resist6rs. If the values
of all resistors are doubled, the values of the node voltages
(a) will become half
(b) will remain unchanged
(c) will become double
(d) cannot be determined unless the circuit configuration and the values of the resistors
are known

35. Consider the following statements regarding the fundamental component f1, (t)
of an arbitrary periodic signal f(t):
It is possible for
1. the amplitude of f1 (t) to exceed the peak value of f(t).
2. f1 (t) to be identically zero for a non-zero f(t).
3. the effective value of f 1(t) to exceed the effective value of f(t).
Which of these statements is/are correct?
(a) 1 alone
(b) 1 and 2
(c) 2 and 3
(d) 1 and 3

36. Two coils have .elf-inductances of 0.09 H and 0.01 H and a mutual inductance of
0.015 H. The coefficient of coupling between the coils is
(a) 0.06
(b) 0.5
(c) 1.0
(d) 0.05

37. A transmission line having 50 Ohms impedance is terminated in a load of (40 +j
30)Ohms . The VS WR is
(a) j 0.033
(b) 0.8+j 0.6
(c) 1
(d)2

38. A vertical wire of 1 m length carries a current of 1 A at 10MHz. The total radiated
power is nearly
(a) 0.13W
(b) 0.88W
(c) 7.3W
(d) 73W

39. A cavity resonator can be represented by
(a) an LC circuit
(b) an LCR circuit
(c) a lossy inductor
(d) a lossy capacitor

40. The skip distance is
(a) same for each layer
(b) independent of frequency
(c) independent of the state of ionisation
(d) independent of transmitted power

Answers :

1 b
2 c
3 d
4 b
5 c
6 c
7 a
8 d
9 b
10 b
11 c
12 d
13 b
14 b
15 a
16 a
17 a
18 a
19 d
20 a
21 b
22 a
23 d
24 a
25 d
26 d
27 b
28 a
29 b
30 b
31 b
32 d
33 b
34 c
35 a
36 b
37 d
38 d
39 a
40 a

Friday, December 10, 2010

NTPC SAMPLE QUESTION PAPER



1. What is causal system?
2. Shunt reactor is used in EHV transmission line for
3. 20w, 40W, & 200w lamps are connected to three phases if neutral wire breaks then which lamp will fuse first? 1) 20 2)40 3)200 three lamps will fuse together.
4. Synchronous machine can be operated at both lagging and leading power factor
5 What does synchronous speed mean?
6. Frequency of emf generated per rotation of rotor is equal to….
7. DC machine having wave winding is wounded as lap winding what will be the effect on emf generated

8 Which is remain unchanged in transformer action?
9. In transformer windings are connected………….?

10. In general how transformer is rated?

11. What is given on the name plate of motor? 1) KW 2) KVA 3) output shaft power

12. Short circuit test of transformer gives what?

13. Transformer core are laminated for what purpose?

14. What is supply voltage for heavy industry .1) 33KV 2) 11KV 3) 132 KV 4) 66KV

15. Basic structure SCR as a two transistor i.e. how they are connected?

16. What is Triac?

17. System admittance is (G+jB) what is reactive power absorbed if the voltage is V KV? (1) V (square)*B (2) V (square)*g ….

18. In series R-L circuit what is phase difference between the voltage drop across R and L?

19. Power factor is cosine (delta ) delta is the angle between 1) phase voltage phase current 2)

Line voltage lone current 3) phase voltage line current 4) line voltage phase current.

20. Laplace of exp (-at)?

21. For series R-L-C circuit the load will be capacitive if the frequency is 1) greater than the resonant frequency 2) less than the resonant frequency 3)….

22. In Wien’s bridge which circuit elements determine the frequency range?

23. What is the output if two booster having duty cycle K and (K-1) are connected in series?

24. If a DC shunt motor is loaded from unloaded condition what will be effect of on terminal voltage?

25. A second wire system having one pole one right half of the s-plane. When the system will be stable?

26. A system having repetitive pole what will be effect on the gain at the cross over frequency?

27. Hollow conductor is used to reduce corona loss how does it reduce the loss?

28. In DC machine how voltage is related to flux?

29. Nature of current and voltage in the armature and at the terminal in DC machine.

30. Motor acts on the principle of …………..rule

31. Which instrument measure both ac and dc?

32. How the rotation of induction motor is reversed?

33. If 3-phaseof a 3- phase balance load are reversed what will be the effect on the line current?

34. If the rating of VAR absorber is 50MVAR at 400KV. What will the VAR absorbed by the absorber at 300KV?

35. In regenerative breaking of DC series motor what is done?

36. Definitions of Fourier transform?

37. Laplace of f(t) is F(S) what is Laplace of f(t+T) .

38. Z-transform of sampled function x(n) for n>0.

39. Laplace transform of impulse function.

40. Z-transform of unity.

41. How many slip rings are there in 3phase synchronous motor?

42. How the speed of synchronous motor is controlled?

43. Speed control of induction motor?

44. When power supply is supplied to heater coil it glows while simple wire does not glow. Why?

45. A synchronous generator having inertia constant 4 and having rating of 100MVA. What will be energy stored by the machine?

46. A transformer having ratio 20:1. The secondary load is 0.6 ohm and the voltage across it is 6 V what will be the primary current?

47. A RC circuit having r=0.8ohm, c=2.5micofarad what will be the time constant?

48. Find load impedance if c=0.1 micro farad?

49. Two capacitors connected in series the equivalent capacitance is 0.03uf and when connected in parallel the equivalent capacitance is 0.16uf find out the ratio of the two capacitance?

50. An L-c circuit having frequency 1/sqrt (LC) what will the equivalent impedance?

51. An inverting op-am having input with resistance in series and a capacitance in feedback operates as a……………….?

52. A current having fundamental and third harmonics what will be the rms value of the current?

53. Peak to peak value of voltage if rms voltage is 100V.

54. Rms voltage.

55. What is the approx efficiency of nuclear power plant?

56. What is the average current of a single phase full wave rectifier firing at angle alpha?

57. What is the function of freewheeling diode?

58. When SCR stops conduction? (holding current)

59. For measuring current why shunt resistance is used?

60. For economic operation of plant what is the condition?(taking into account the penalty factor)

61. Incremental fuel cost of two plants is given and a load is given. Find out the load sharing for economic operation of the plant?

62. A two port network is represented by ABCD parameters. What will be condition for the two port network to be symmetrical?

63. Size of the conductor is determined by ……………….

64. Which Surface is suitable for grounding?

BSNL JTO Previous paper

1. For a parallel plate capacitor which is being charged out of the following the incorrect statement is –

a). Energy stored in the capacitor does not enter it through the connecting wire through the space around the wires and plates of capacitor.

b.) Rate at which energy flows into this volume is equal to the integration of the poynting vector over the boundary of the volume between the plates.

c.) The poynting vector points everywhere radially outward of the volume between plates.

d.) The poynting vector points everywhere radially into the volume between the plates.

2. The presence of alkali oxides in alumino silicate ceramics is likely to result in dielectric breakdown due to –

a. )Polarization

b.)Conductivity

c.)Structural homogeneties

d) Ionization

3. Which of the following will serve as a donor impurity in silicon –

a.)Boron

b) Indium

c) Germanium

d) Antimony

4. Electrical contact materials used in switches, brushes and relays must possess –

a)High thermal conductivity and high melting point

b) Low thermal conductivity and low melting point

c) High thermal conductivity and low melting point.

d) Low thermal conductivity and high melting point.

5. The Maximum spectral response of the germanium and silicon is in the –

a) infrared region

b) ultraviolet region

c) visible region

d) x-ray region

6. For an insulating material, dielectric strength and dielectric loss should be respectively –

a) high and high

b) low and high

c.) high and low

d.) low and low

7. In a distortion factor meter, the filter at the front end is used to suppress

a.) odd harmonics

b.) even harmonics

c.) fundamental component

d.) dc component

8. The coefficient of coupling between two air core coils depends on –

a). mutual inductance between two coils only

b). self inductances of the two coils only

c). mutual inductance and self inductances of the two coils

d.) none

9. Modern capacitors which have high capacitance in small size use a dielectric of –

a.) paper

b.) rubber

c.) ceramic

d.) Mylar

10. In any atom the potential energy of an orbiting electron is –

a.) always positive

b.) always negative

c.) sometime positive, sometime negative

d.) numerically less than its kinetic energy

11. A DE MOSFET differs from a JFET in the sense that it has no –

a.) channel

b.) gate

c.) P-N junctions

d.) substrate

12. The advantage of a semiconductor strain gauge over the normal strain gauge is that

a.) it is more sensitive

b.) it is more linear

c.) it is less temperature dependent

d.) it’s cost is low

13. Barrier potential in a P-N junction is caused by –

a.) thermally generated electrons and holes

b.) diffusion of majority carriers across the junction

c.) migration of minority carriers across the junction

d.) flow of drift current

14. When an NPN transistor is properly biased then most of the electrons from the emitter –

a.) recombine with holes in the base

b.) recombine in the emitter itself

c.) pass through the base to the collector

d.) are stopped by the junction barrier

15. The value of r when a transistor is biased to cut off is –

a.) 0.5

b.) 0

c.) 1.0

d.) 0.8

16. A UJT can –

a.) be triggered by any one of it’s three terminals

b.) not be triggered

c.) be triggered by two of its three terminal only

d.) be triggered by all of its terminals only

17. An SCR can only be turned off via it’s –

a.) cathode

b.) anode

c.) gates

d) none

18. Gold is often diffused into silicon DN junction devices to –

a.) increase the recombination rate

b.) reduce the recombination rate

c.) make silicon a direct gap semiconductor

d.) make silicon semi-metal

19. With n nodes and b branches a network will have –

a.) (b + n) links

b.) b – n + 1 links

c.) b – n – 1 links

d.) b + n + 1 links

20. When a network has 10 nodes and 17 branches in all then the number of node pair voltages would be –

a.) 7

b.) 9

c.) 10

d.) 45

21. A two port network having a 6 dB loss will give –

a.) an output power which is one – quarter of the input power

b.) an output power which is one – half of the input power

c.) an output voltage which is 0.707 of the input voltage

d.) an output power which is 0.707 of the input power

22. While transporting a sensitive galvanometer –

a.) the terminals are kept shorted

b.) critical damping resistance is connected across the terminals

c.) the terminals are kept open circuited

d.) it does not matter as to what is connected across the terminals

23. A T type attenuator is designed for an attenuation of 40 dB and terminating resistance of 75 ohms. Which of the following values represent full series and R1 and shunt arm R2 ?

1. R1 = 147W 2. R1 = 153W

3. R2 = 1.5W 4. R2 = 3750W

a..) 1 and 3

b.). 1 and 4

c.). 2 and 3

d..) 2 and 4

24. For a transmission line, the characteristic impedance with inductance 0.294mH/m and capacitance 60pF/m is –

a..) 49w

b.). 60w

c..) 70w

d..) 140w

25. When the graph of a network has six branches with three tree branches then the minimum number of equations required for the solution of the network is –

a..) 2

b..) 3

c..) 4

d..) 5

26. Consider the following statement for a 2-port network

1. Z11 = Z22 2. h12 = h21

3. Y12 = -Y21 4. BC – AD = -1

then the network is reciprocal if and only if –

a..) 1 and 2 are correct

b.) 2 and 3 are correct

c.) 3 and 4 are correct

d.). 4 alone is correct

27. As a network contains only independent current sources and resistors then if the values of all resistors are doubled then th
e values of the node voltages are –

a.) will become half

b.) will remain uncha

c.). will become double

d.). cannot be determined unless the circuit configuration and the values of the resistors are known

28. The energy of electric field due to a spherical charge distribution of radius r and uniform charge density in vacuum is-

29. Maxwell’s divergence equation for the magnetic field is given by

30. When a short grounded vertical antenna has a length L which is 0.05 l at frequency f and if it’s radiation resistances at f is R Ohms, then it’s radiation resistance at a frequency 2f will be –

a). R/2 ohms

b). R ohms

c). 2R ohms

d). 4R ohms

31. In a cylindrical cavity resonator, the two modes which are degenerate would include

a.) TE111 and TM111

b). TE011 and TM011

c). TE022 and TM111

d). TE111 and TM011

32. When an antenna of input resistance 73 ohm is connected to a 50-ohm line and if the losses are ignored then it’s efficiency will be nearly

a). 0.19

b). 0.81

c). 0.97

d). 1.19

33. If an isolated conducting sphere in air has radius = 1/ 4pqe0 it capacitance will be

a). Zero

b). IF

c). 4pF

d). OF

34. When a dominant mode wave guide not terminated in it’s characteristic impedance is excited with a 10 GHz signal then if ‘d’ is the distance between two successive minima of the standing wave in the guide then

a). d = 1.5 cm

b). d is less then 1.5 cm

c). d is greater than 1.5 cm

d). d = 3cm

35. When a dipole antenna of l/8 length has an equivalent total loss resistance of 1.5 W then the efficiency of the antenna is

a). 0.89159 %

b). 8.9159 %

c). 89.159 %

d). 891.59 %

36. In commercial FM broadcasting, the maximum frequency deviation is normally

a). 5 KHz

b). 15 KHz

c). 75 KHz

d). 200 KHz

37. Weins bridge is used for measurement of frequency in the applied voltage waveform is measurement of frequency in the applied voltage waveform is –

a). sinusoidal

b). square

c). rectangular

d). triangular

38. Strain gauge is –

a). not a transducer

b). an active transducer

c). not an electronic instrument

d). none

39. A high Q coil has –

a). large band width

b). high losses

c). low losses

d). flat response

40. In the case of an instrument reading of 8.3V with a 0 to 150 voltmeter having a guaranteed accuracy of 1% full scale reading, the percentage limiting error is –

a). 1.810%

b). 0.181%

c). 18.10%

d). 0.0018%

41. The ‘h’ parameter equivalent circuit of a junction transistor is valid for –

a). High frequency, large signal operation

b.) High frequency, small signal operation

c.) Low frequency, small signal operation

d). Low frequency, large signal operation

42. A system is causal if the output of any time depends only on –

a.) Values of input in the past and in the future

b). Values of input at that time and in the past

c). Values of input at that time and in the future

d). None

43. A iron cored choke is a –

a). Linear and active device

b). Non linear and passive device

c). Active device only

d). Linear device only

44. Poynting vector wattmeter uses –

a). Seebeck effect

b). Ferranti effect

c). Induction effect

d). Hall effect

45. Which one of the following is not a transducer in the true sense ?

a). Thermocouple

b). Piezoelectric pick – up

c). Photo voltaic cell

d). LCD

46. The term used to denote a static device that converts ac to dc, dc to ac, dc to dc or ac to ac is –

a). Converter system

b). Inverter

c). Chopper

d). Thyristor

47. It is an unidirectional device that blocks the current flow from cathode to anode –

a). SCR

b). PCR

c). VCR

d). DCR

48. An ideal constant current source is connected in series with an ideal constant voltage source. Considering together the combination will be a –

a). constant voltage source

b). constant current source

c). constant voltage and a constant current source or a constant power source

d). resistance

49. Anode current in an thyristor is made up of –

a). electrons only

b). electrons or holes

c). electrons and holes

d). holes only

50. For a pulse transformer, the material used for its core and the possible turn ratio from primary to secondary are respectively –

a). ferrite : 20 : 1

b). laminated iron : 1 : 1

c). ferrite : 1 : 1

d). powdered iron : 1 : 1

51. A converter which can operate in both 3 pulse and 6 pulse modes is a –

a.) 1 phase full converter

b). 3 phase half wave converter

c). 3 phase semi converter

d). 3 phase full converter

52. A single phase CSI has capacitor C as the load. For a constant source current, the voltage across the capacitor is –

a.) square wave

b.) triangular wave

c )step function

d.) pulsed wave

53. A single phase full wave midpoint thyristor converter uses a 230/200V transformer with centre tap on the secondary side. The P.I.V per thyristor is –

a). 100V

b). 141.4V

c). 200V

d). 282.8V

54. In dc choppers for chopping period T, the output voltage can be controlled by FM by varying –

a). T keeping Ton constant

b). Ton keeping T constant

c). Toff keeping T constant

d.) None of the above

55. From the hot metal surface electrons escape because

a). of change of state from metal to gas due to heat.

b). of change of stats from gas to metal.

c). the energy supplied is greater than the work function .

d). the energy is greater than Fermi level.

56. The most common device used for detection in radio receivers is –

a). amplifier

b). triode

c). diode

d). transistor

57. In a full wave rectifier the negative point in a circuit is

a). Either cathode

b). Eith
er anode

c). The central tap on the high voltage secondary

d). Either plate

58. Negative feedback amplifier has a signal corrupted by noise as its input. The amplifier will-

a). Amplify the noise as much as the signal

b). Reduce the noise

c). Increase the noise

d). Not effect the noise

59. Match the given feedback circuit with it’s proper nomenclatures

a). Current series feedback

b). Current shunt feedback

c). Voltage series feedback

d). Voltage shunt feedback

60. Class A amplifier is used when

a). No phase inversion is required

b). Highest voltage gain is required

c). dc voltages are to be amplified

d). Minimum distortion is desired

61. Identify the correct match for the given transistor

a). Enhancement type P channel MOSFET

b). Depletion type N channel MOSFET

c). Enhancement type N channel MOSFET

d). Depletion type P channel MOSFET

62. In case a signal band limited to fm is sampled at a rate less than 2fm, the constructed signal will be

a). Distortionless

b). Small in amplitude

c). Having higher frequencies suppressed

d). Distorted

63. Quad 2 input AND gates IC No is –

a). 7411

b). 7404

c). 7400

d). 7408

64. Registers in which data is entered or taken out in serial form are referred as –

a). left shift register

b). right shift register

c). shift registers

d). none of the above

65. The expression can be simplified to

b.) AB + BC + CA

66. An ideal power supply consist of –

a) . Very small output resistance

b) . Zero internal resistance

c) . Very large input resistance

d) . Very large output resistance

67. The linearity error for a digital input is indicated by –

68. Register and counters are similar in the sense that they both –

a). count pulses

b). store binary operation

c). shift registers

d). made from an array of flip flops and gates integrated on a single chip

69. In the 8421 BCD code the decimal number 125 is written as –

a). 1111101

b). 0001 0010 0101

c). 7D

d). None of the above

70. In D/A converter, the resolution required is 50mv and the total maximum input is 10v. The number of bits required is –

a). 7

b). 8

c). 9

d). 200

71. On differentiation unit impulse function results in —

a). Unit parabolic function.

b). Unit triplet.

c). Unit doublet.

d). Unit ramp function.

72. Read the following;

i. Routh Hermitz`s criterion is in time domain.

ii. Root locus plot is in time domain.

iii. Bode plot is in frequency domain.

iv. Nyquist criterion is in frequency domain.

a). 2, 3, and 4 are correct

b). 1, 2 and 3 are correct

c). 3 and 4 are correct

d). All four are correct.

73. The maximum phase shift that can be provided by a lead compensator with transfer function.

a). 150

b). 450

c). 300

d). 600

74. The correct sequence of steps required to improve system stability is –

a). Insert derivative action, use negative feedback, reduce gain.

b). Reduce gain, use negative feedback, insert derivative action.

c). Reduce gain, insert derivative action, use negative feedback.

d). Use negative feedback, reduce gain, insert derivative action.

75. Identity slope change at w = 10 of the magnitude v/s frequency characteristic of a unity feedback system with the following open-loop transfer function –

a). –40dB/dec to –20dB/dec

b). 40dB/dec to 20dB/dec

c). –20dB/dec to –40dB/dec

d). 40dB/dec to –20dB/dec

76. In the feedback control system the loop transfer function is given by –

Number of asymptotes of its root loci is

a). 1

b). 2

c). 3

d). 4

77. In a closed – loop transfer function the imaginary axis intercepts of the root loci will be –

78. Considering the following statement :

In a magic tee

1. the collinear arms are isolated from each other

2. one of the collinear is isolated from the E-arm

3. one of the collinear arm is isolated from the H-arm

4. E-arm and H-arm are isolated from each other.

Of these statements

a) 1 and 2 are correct

b). 1 and 3 are correct

c). 1 and 4 are correct

d). 2 and 3 are correct

79. In 1965 first geostationary satellite was launched called –

a). ANIK

b). EARLY BIRD (Intel sat -1)

c). WESTAR

d). MOLNIYA

80. — watt of power is received from sun per m2 surface area of a geosynchronous satellite

a). 100

b). 500

c). 2000

d). 1000

81. The ripple factor in an LC filter

a). Increases with the load current

b). Increases with the load resistance

c). Remains constant with the load current

d). Has the lowest value

82. In different parts of the country identical telephone numbers are distinguished by their –

a). Language digits

b). Access digits

c). Area codes

d). Central office codes

83. Amplitude modulation is used for broadcasting because

a). it is move noise immune than other modulation systems

b). compared with other systems it requires less transmitting power

c). its use avoids receiver complexity

d). no other modulation system can provide the necessary bandwidth for high fidelity

84. The amplifiers following the modulated stage in a low level modulation AM system be

a). linear amplifier

b). harmonic generators

c). class C power amplifiers

d). class B untuned amplifiers

85. In a radar system maximum unambiguous range depends on

a). maximum power of the transmitter

b). pulse repetition frequency

c). width of the transmitted pulse

d). sensitivity of the radar receiver

86. In composite video waveform the function of the serrations, is to

a). equalize the charge in the integrator before the start of vertical retrace.

b). help vertical synchronization

c). help horiz
ontal synchronization.

d). simplify the generation of the vertical sync pulse

87. The frequency range 30MHz – 300MHz is –

a). medium frequency

b). very high frequency

c). super high frequency

d). Infrared frequency

88. Which wave cannot exist inside wave guide –

a.) TE

b). TM

c). TEM

d). HE

89. Ionosphere layer of earth is situated at –

a). upto 18kms from earth

b). from 18 to 70 km

c). 70 to 500 km

d). above 500 km

90. A two cavity klystron tube is a –

a). velocity modulated tube

b). frequency modulated tube

c). Amplitude modulated tube

d). simple triode

91. As the thermal noise get doubled due to the increase in a resistance the noise power get –

a). doubled

b). quadrupted

c). unchanged

d). halved

92. Which one is a cross field tube –

a). Klystron

b). Reflex Klystron

c.) Magnetron

d.) TWT

93. The degree of coupling depends on –

a). size of hole

b). location of holes

c). size and location of holes

d). not depend on size or location of hole

94. The thermal noise depends on –

a). direct current through device

b.) resistive component of resistance

c). reactive component of impedance

d) load to connected

95. The charge on a hole is –

96. In a radio receiver the IF amplifier

a.) is tuned above the stations incoming frequency

b). amplifies the output of local oscillator

c). is fixed tuned to one particular frequency

d). can be tuned to various isolate frequencies

97. A duplexer is used to

1. ) couple two antennas to a transmitter without interference
2. ) isolate the antenna from the local oscillator
3. ) prevent interference between two antennas connected to a receiver
4. ) use an antenna for reception or transmission without interference

98. Intel’s 8085 microprocessor chip contains

a). seven 8 bit registers

b). 8 seven bits registers

c). seven 7

d). eight 8

99. Boolean algebra is based on –

a). numbers

b). logic

c). truth

d). symbols

100. When A = 0, B = 0, C = 1 then in 2 input logic gate we get – - gate

a). XOR

b). AND

c). NAND

d). NOR

101. With the beginnings of space travel, we entered a new – -

a). Era of great history

b). List

c). Book

d). Year

102. An – - though it mourns the death of someone, need not be sad.

a). Funny poem

b). Newspaper article

c). Orthodox talk

d). Elegy

103. If stare is glance so gulp is –

a). Sip

b). Tell

c). Salk

d). Admire

104. He hardly works means –

a). The work is hard

b). He is hard

c). The work is easy

d). He work very little

105. Give the opposite word for pulchritude –

a). antipathy

b). unsightliness

c). inexperience

d). languor

106. Nanometre is – - – - part of a metre.

a). Millionth

b). Ten millionth

c). Billionth

d). Ten billionth

107. Malaria affects

a). Liver

b). Spleen

c). Intestine

d). Lungs

108. Sindhu Rakshak is a/an

a). Aircraft carrier

b). Submarine

c). Multiple-purpose fighter

d). Anti-aircraft gun

109. With which subject is "Dada Saheb Phalke Award" associated?

a). Best film director

b). Best musician

c). Best documentary

d). Best work relating to promotion of Indian film Industry

110. Who developed the branch of mathematics known as Calculus?

a). Aryabhatta

b). Newton

c). Einstein

d). Archimedes

111. In which state is Kanha Park situated?

a). M.P.

b). U.P.

c). Assam

d). W. Bengal

112. Which day is observed as Human Rights Day?

a). 24th October

b). 4th July

c). 8th August

d.) 10th December

113. The Kailash Temple at Ellora is a specimen of

a). Gupta architecture

b). Rashtrakuta architecture

c). Chalukya architecture

d). Chola architecture

114. When the two Houses of Parliament differ regarding a Bill then the controversy is solved by

a). Joint sitting of the two Houses

b). President of India

c). Prime Minister of India

d). By a special committee for the purpose

115. Which of the following is not the work of Kalidasa?

a). Meghdoot

b). Raghuvansha

c). Sariputra Prakarma

d). Ritushamhara

116. Amir Khusro was the famous poet and aesthete of

a). Akbar the Great

b). Mahmud Ghaznvi

c). Shah Jahan

d.) Alauddin Khilji

117. The words ‘Satyameva Jayate’ have been taken from

a). Vedas

b). Bhagwad Gita

c). Mundaka Upanishada

d). Mahabharata

e). None of these

118. Which of the following countries was the first to develop a neutron bomb?

a). USA

b). USSR

c). China

d). Pakistan

119. "Kathakali" dance is connected with

a). Kerala

b). Rajasthan

c). Uttar Pradesh

d). Tamil Nadu

120. The term "Ashes" is associated with

a). Hockey

b). Cricket

c). Soccer

d). None of these

Sunday, December 5, 2010

SAIL MT COMPUTER SCIENCE QUESTIONS

1. Tn a packet switching network, packets are routed from source to destination along a single path having two intermediate nodes. If the message size is 24 bytes and each packet contains a header of 3 bytes, then the optimum packet size is
(a)4
(b)6
(c)7
(d)9

2. Suppose the round trip propagation delay for a 10 Mbps Ethernet having 48-bit jamming signal is 46.4 micro seconds The minimum frame size is?
(a) 94
(b) 416
(c) 464
(d) 512

3. For which one of the following reasons does Internet Protocol (IP) use the time-to-live (TTL) field in the IP datagram header?
(a) Ensure packets reach destination within that time
(b) Discard packets that reach later than that time
(c) Prevent packets from looping indefinitely
(d) Limit the time for which a packet gets queued in intermediate routers

4. Station A uses 32 byte packets to transmit messages to Station B using a sliding window protocol. The round trip delay between A and B is 80 milliseconds and the bottleneck bandwidth on the path between Aand B is 128 kbps. What is the optimal window size that A should use?
(a) 20
(b) 40
(c) 160
(d) 320

5. Two computers C1and C2 are configured as follows.
C1has IP address 203. 197.2.53 and netmask 255.255. 128.0.
C2 has IP address 203.197.75.201 and netmask 255.255.192.0.
Which one of the following statements is true?
(a) C1 and C2 both assume they are on the same network
(b) C2 assumes Cl is on same network, but C1 assumes C2 is on a different network
(c) C1 assumes C2 is on same network, but C2 assumes C1 is on a different network
(d) C1 and C2 both assume they are on different networks

6. Station A needs to send a message consisting of 9 packets to Station B using a siding window (window size 3) and go-back-n error control strategy. All packets are ready and immediately available for
transmission. If every 5th packet that A transmits gets lost (but no acks from B ever get lost), then what is the number of packets that A will transmit for sending the message to B?
(a)12
(b)14
(c)16
(d)18

7. For the given connection of LANs by bridges, which one of the following choices represents the depth first traversal of the spanning tree of bridges?
(a) B1,B5,B3,B4,B2
(b) B1,B3,B5,B2,B4
(c) B1, B5, B2, B3, B4
(d) B1,B3,B4,B5,B2

8.The micro instructions stored in the control memory of a processor have a width of 26 bits. Each micro-instruction is divided into three fields: a micro-operation field of 13 bits, a next address field (X), and a MUX select field (Y). There are 8 status bits in the inputs of the MUX.

How many bits are there in the X and Y fields, and what is the size
of the control memory in number of words?
(a)10,3,1024
(b) 8, 5, 256
(c) 5, 8 , 2048
(d) 10, 3, 512

9. A hard disk with a transfer rate of 10 M bytes/second is constantly transferring data to memory using DMA. The processor runs at 600 MHz, and takes 300 and 900 clock cycles to initiate and complete DMA transfer respectively. If the size of the transfer is 20 Kbytes, what is the percentage of processor time consumed for the transfer operation?
(a)5.0%
(b)1.0%
(c)0.5%
(d) 0.1%

10. A 4-stage pipeline has the stage delays as 150, 120, 160 and 140 nanoseconds respectively. Registers that are used between the stages have a delay of 5 nanoseconds each. Assuming constant clocking rate, the total time taken to process 1000 data items on this pipeline will be
(a) 120.4 microseconds
(b) 160.5 microseconds
(c) 165.5 microseconds
(d) 590.0 microseconds

11. Which one of the following is true for a CPU having a single interrupt request line and a single interrupt grant line?
(a) Neither vectored interrupt nor multiple interrupting devices are possible
(b) Vectored interrupts are not possible but multiple interrupting devices are possible
(c) Vectored interrupts and multiple interrupting devices are both possible
(d) Vectored interrupt is possible but multiple interrupting devices are not possible

12. Normally user programs are prevented from handling 110 directly by I/O instructions in them. For CPUs having explicit I/O instructions, such I/O protection is ensured by having the I/O instructions privileged. In a CPU with memory mapped I/O, there is no explicit I/O instruction. Which one of the following is true for a CPU with memory mapped I/O?
(a) I/O protection is ensured by operating system routine(s)
(b)I/O protection is ensured by a hardware trap
(c) I/O protection is ensured during system configuration
(d) I/O protection is not possible

13. What is the swap space in the disk used for?
(a) Saving temporarily html pages
(b) Saving process data
(c) Storing the super-block
(d) Storing device drivers

14. Increasing the RAM of a computer typically improves performance because
(a) Virtual memory increases
(b) Larger RAMs are faster
(c) Fewer page faults occur
(d) Fewer segmentation faults occur

15.

Solutions:

1 d
2 d
3 b
4 b
5 c
6 c
7 a
8 a
9 d
10 c
11 b
12 a
13 b
14 c
15 d

SAIL ELECTRONICS ENGINEERING QUESTIONS

1.Consider two samples of silicon semiconductor identical in all respects except that one is uniformly doped with1015 cm10-3 donor impurity atoms (Sample A) and the other is non-uniformly doped with donors from one side such that Nd(x) = N0 e -ax (sample B). Let a = 1 hm-1 and N0= 1017 cm-3 . Consider the following sample B.
1. Sample A will not have any current at equilibrium but current will flow out of sample B
2. Both samples will have built-in electric, field
3. Sample A will have zero built-in electric field whereas sample B will have a constant built-in electric field
4. No current will flow at equilibrium from either sample A or sample B
Select the correct answer using the codes given below:
Codes:
(a)1 and 2
(b) 1 and 3
(c) 1 and 4
(d) 3 and 4

2. Consider the following statements:
The temperature dependence of resistivity of a sample of N-type silicon is based upon carrier concentration and carrier mobility variations with temperature
because
1. the resistivity of silicon increases with temperature.
2. the mobility decreases with temperature
3. the carrier concentration increases with temperature
4. the resistivity of silicon decreases with temperature
Which of these statements are correct?

(a)1,2and3
(b) 2,3and
(c)1 and2
(d) 3and 4

3. The unit of mobility is
(a)m2V-1s-1
(b) mV-1s-1
(c)Vsm-1
(d) Vms-1

4. The Haynes-Shockley experiment enables one to determine the
(a) diffusion coefficient of majority carriers
(b) effective mass of the minority carriers
(c) mobility of the minority carriers
(d) lifetime of the majority carriers

5. The Hall constant in p-Si bar is given by 5 x 103 cm35/Coloumb The hole concentration in the bar is given by
(a) 1.00 x 1015/ cm3
(b) 1.25 x 1015/ cm3
(c) 1.50 x 1015/ cm3
(d) 1.60 x 1015/ cm3 -

6. In an extrinsic semiconductor, the Hall coefficient RH
(a) increases with increase of temperature
(b) decreases with increase of temperature
(c) is independent of the change of temperature
(d) changes with the change of magnetic field

7. Consider a semiconductor bar having square cross-section. Assume that holes drift in the positive x-direction and a magnetic field is applied perpendicular to the direction in which holes drift. The sample will show
(a) a negative resistance in positive y-direction
(b) a positive voltage in positive y-direction
(c) a negative voltage in positive y-direction
(d) a magnetic field in positive y-direction

8. The change in barrier potential of a silicon p-n junction with temperature is
(a)0.025 Volts per degree C
(b) 0.250 Volts per degree C
(c)0.030 Volts per degree C
(d) 0.014 Volts per degree C

9.Moor’s law relates to
(a) speed of operation of bipolar devices
(b) speed of operation of MOS devices
(ç) power rating of MOS devices
(d) level of integration of MOS devices

10. The colour T. V. picture signal is a
(a) single-channel, one-dimensional signal
(b) single-channel, three-dimensional signal
(c) three-channel, one-dimensional signal
(d)three-channel, three-dimensional signal

11 Consider the following statements:
1. Fourier transform is special case of Laplace transform.
2. Region of convergence need not be specified for Fourier transform.
3. Laplace transform is not unique unless the region of convergence is specified.
4. Laplace transform is a special case of Fourier transform.
Which of these statements are correct?
Codes:
(a)2 and 4
(b) 4 and 1
(c)4, 3 and 2
(d) 1, 2 and 3

12. The units of the spectrum obtained by Fourier transforming the covariance function of a stationary stochastic process is?
(a)power per Hertz
(b) energy per Hertz
(c)power per second
(d) energy per second

13. The maximum power that a 12 V d.c. source with an internal resistance of 20 Ohms can supply to a resistive load is ?
(a)12W
(b) 18W
(c)36W
(d) 48W

14. Consider the following statements associated with the Superposition theorem:
1. It is applicable to d.c. circuits only.
2. It can be used to determine the current in a branch or voltage across a branch.
3. It is applicable to networks consisting of more than one source.
4. It is applicable to networks consisting of linear and bilateral elements.
Which of these statements are correct?
(a)1, 2 and 3
(b) 2, 3 and 4
(c)3, 4 and 1
(d) 4, 1 and 2

15. Which one of the following statements is NOT a property of R-L driving point
impedance?
(a) The first critical frequency at the origin is a zero
(b) The last critical frequency is a pole
(c) The impedance at S =infinity is always less than the impedance at S = zero
(d) The slope of the impedance curve is positive at all points

16. In a network containing resistances and reactances the roots of the characteristic
equation give for the circuit
(a)the forced response
(b) the total response
(c)the natural response
(d) the damped response

17. Consider the following:
Energy storage capability of basic passive elements is due to the fact that
1. resistance dissipates energy
2. capacitance stores energy
3. inductance dissipates energy
Which of the above is/are correct?
(a)1, 2 and 3
(b) 1 and 3
(c) 3 alone
(d) 1 and 2

18. √L/C has the dimension of
(a)time
(b) capacitance
(c)inductance
(d) resistance

19. A network N’ is dual of network N if
(a) both them have same mesh equations
(5) both of them have the same node equations
(c) mesh equations of one are the node equations of the other
(d) KCL and KVL equations are the same

20. The input impedance of a short circuited quarter wave long transmission line is
(a) purely reactive
(b) purely resistive
(c) dependent on the characteristic impedance of the line
(d) none of the above

21. For a wave propagating in an air filled rectangular waveguide
(a) guided wavelength is never less than the free space wavelength
(b) wave impedance is never less than the free space impedance
(c) TEM mode is possible if the dimensions of the waveguide are properly chosen
(d) Propagation constant is always a real quantity

22. Consider the following statements with reference to Brewster angle:
1. For oblique incidence at a boundary, there is no reflected wave when the incident wave is vertically polarized.
2. Brewster angle can occur only at the boundary of a perfect conductor.
3. For a horizontally polarized wave, there is no Brewster angle.
4. When the incident wave is not fully vertically polarized, there will be a reflected component which is horizontally polarized.
Which of these statements are correct?
(a)1,2and3
(b) 2,3and4
(c)3, 4 and 1
(d) 4, 1 and 2

23. When a particular mode is excited in a wave-guide, there appears an extra electric component in the direction of propagation. The resulting mode is
(a) transverse-electric
(b) transverse-magnetic
(c) longitudinal
(d) transverse-electromagnetic

24. The most suitable primary standard for frequency is
(a)Rubidium vapour standard
(b) Quartz standard
(c)Hydrogen maser standard
(d) Caesium beam standard

25. Horizontally mounted moving iron instruments employ
(a)Eddy current damping
(b) Air friction damping
(c)Fluid friction damping
(d) Electromagnetic damping

26. There are four types of controlled sources, namely VC VS, VC CS, CC CS, CC VS.
It is required to select a proper controlled source configuration for interfacing
the output of a high-impedance microphone to a low impedance loudspeaker.
The proper source will be
(a) VC VS (Voltage Controlled Voltage source)
(b) VC CS (Voltage Controlled Current Source)
(c) CC CS (Current Controlled Voltage Source)
(d) CC VS (Current Controlled Voltage Source)

27. Some of the functional building blocks of a measurement system are:
Primary Sensing Element (PSE)
Variable Conservation Element (VCE),or Transducer
Data Transmission Element (DTE)
Variable Manipulation Element (VME)
Data Presentation Element (DPE)

The correct sequntial connection of the functional building blocks for an
electronic pressure gauge will be
(a)PSE, VME, VCE, DPE, DTE
(b) PSE, VCE, VME, DTE, DPE
(c)DTE, DPE, VCE, PSE, VME
(d) PSE. VCE, DTE, DPE, VME

28. According to Guassian statistical analysis, if the confidence level is 0.80, then the values lying outside the confidence interval are
(a)1 in 5
(b) 1 in 10
(c)1 in 20
(d) 8 in 10

29. The true rams. voltmeter employs two thermocouples in order to
(a) prevent drift
(b) increase the accuracy
(c) increase the sensitivity
(d) cancel out the nonlinear effects of first thermocouple

30. A certain oscilloscope with 4cm by 4cm screen has its own sweep output fed to its input. If the x and y sensitivities are same, the oscilloscope will display a
(a) saw-tooth wave
(b) triangle wave
(c)diagonal line
(d) horizontal line

Answers :

1 d
2 b
3 a
4 c
5 b
6 a
7 b
8 a
9 d
10 b
11 d
12 b
13 b
14 b
15 c
16 c
17 d
18 d
19 c
20 d
21 a
22 c
23 b
24 d
25 b
26 a
27 b
28 a
29 d
30 c

Electrical engineering objective questions

Electrical engineering objective questions and answers for Various Competitive Exams

1.A 10 V battery with an internal resistance of 1 Ohms is connected across a non-linear load whose v-i

characteristic is given by 7 i = v2 + 2v.
The current delivered by the battery is
(a) 2.5A
(b) 5A
(c)6A
(d)7A
2. A Voltage V is applied to an ac circuit resulting in the delivery of a current I. Which of the
following expression would yield the true power delivered by the source ?
1. Real part of V I
2. Real part of VI
3. I 2times the real part of V I

Select the correct answer using the bodes given below:
Codes:
(a) 1 alone
(b) 1 and 3
(c) 2 and 3
(d) 3 alone

3.The current through the current coil of a watt meter is given by, i = (1+2 sin wt) V and the voltage across the pressure coil is, v = (2 +3 sin 2 wt) V The wattmeter will read
(a) 8.00W
(b) 5.05
(c) 2.0W
(d) 1.0W

4. A 3-phase, 3-wire supply feeds a load consisting of three equal resistors connected star. If 01w of the
resistors is open circuited, then the percentage reduction in the load will be
(a) 75
(b) 66.66
(c) 50
(d) 3.33

5. Two identical coils of negligible resistance, when connected in series across a S0Hzfixed voltage source, draw a current of 10 A. When the terminals of one of the coils are reversed, the current drawn is 8A. The coefficient of coupling between the two coils is
(a) 1/100
(b) 1/9
(c) 4/10
(d) 8/10

6. Swamping resistance is a resistance which is added to the moving coil of a meter to
(a) reduce the full – scale current
(b) reduce the temperature error
(c) increase the sensitivity
(d) increase the filed strength

7. A high frequency as signal is applied to a PMMC instrument. If the rms value of the ac signal is 2 V then the reading of the instrument will be ?
(a) zero
(b) 2 V
(c)3.2V
(d)4.2V

8. The resistance of a shunt for a precision grade ammeter can be best measured by
(a) De Sauty bridge
(b) Scherring bridge
(c) Maxwell bridge
(d) Kelvin double bridge

9. Which one of the following has the highest accuracy?
(a) Standard resistance
(b) Standard inductance
(c) Standard capacitance
(d) Standard mutual inductance

10. An indicating instrument is more sensitive if its torque to weight ratio is
(a) much larger than unity
(b) of the order of unity
(c) much less than unity
(d) made deflection – dependent

11. The X- and Y- inputs of a CR0 are respectively V sin wt and -V sin wt. The resulting Lissajous
pattern will be
(a) a straight line
(b) a circle
(c) an ellipse
(d) a figure of eight

12. In a flux meter, the controlling torque is
(a) produced b weights attached to the moving coil
(b) produced by spring
(c) not provided at all
(d) provided by crossed coil mechanism

13. Dummy strain gauge is used in conjunction with the main strain gauge to
(a) calibrate the system
(b) compensate temperature effects
(c) improve sensitivity
(d) reduce strain on the main gauge

14. In a two-watt-meter method of measuring power, one of the watt meters is reading zero watts. The
power factor of the circuit is
(a) zero
(b) 1
(c) 0.5
(d) 0.8

15. half effect device can be used to
(a) multiply two signals
(b) divide one signal by another on an instantaneous basis
(c) add two signals
(d) subtract one signal from another

16. Doppler shift principle is used in the measurement of
(a) temperature
(b) frequency
(c) speed
(d) pressure

17. In distortion factor meter, the filter is used to suppress
(a) dc component
(b) odd harmonics
(c) even harmonics
(d) fundamentals

18. Which of the following measurements can be made with the help of a frequency counter?
1. Fundamental frequency of input signal
2. Frequency components of the input signal at least upto third harmonic
3. lime interval between two pulses
4. Pulse width.
Select the correct answer using the codes given below:
Codes:
(a) 1,3and 4
(b) 1,2and 3
(c) 2and 4
(d) 1 and 2

19. The bandwidth requirement of an FM telemetry channel is
(a) equal to that of an AM telemetry channel
(b) smaller than that an AM telemetry channel
(c) about 100 times that of an AM telemetry channel
(d) about ten times that of an AM telemetry channel

20. The recording head in a magnetic tape responds to
(a) electrical signal and creates a magnetic signal
(b) thermal signal and creates a magnetic signal
(c) magnetic signal and creates an electrical signal
(d) thermal signal and creates an electrical signal.

21. When the input to a system was withdrawn at t= 0, its output was found to decrease exponentially
from 1000 units to 500 units in 1.386 seconds. The time constant of the system is?
(a) 0.500
(b) 0.693
(c) 1.386
(d) 2.000

22. Consider the following statements regarding constructional features of synchros:
1. Synchro repeater has a three-phase stator and three-phase rotor.
2. Disc shaped rotor of the synchro control transformer offers a low reluctance to the magnetic path.
3. Synchro transmitter has a frictionless bearing.
Of these statements
(a) 1,2 and 3 correct
(c) 2 alone is correct
(b) 1 alone is correct
(d) 2 and 3 are correct

23. Which of the following motors would be suitable for use as servomotors?
1. Two-phase induction motor.
2. DC separately excited motor.
3. Single-phase capacitance start induction motor.
4. Universal motor.
5. Single-phase synchronous motors.
Select the correct answer using the codes given below:
Codes:
(a) 1,2,3,4 and 5
(c) 1,2and5
(b) 2,3,and4
(d) 1 and 5

The following items consists of two statements, one labelled the ‘Assertion A’ and the
other labelled the ‘Reason R’. You as to examine these two statements carefully and decided !f the Assertion A and the Reason R are individually true and f so, whether the Reason is a correct explanation of the Assertion. Select your answer to these items using the codes given below and mark your answer sheet accordingly:
Codes:
(a) Both A and R are true and R’is the correct explanation of A.
(b) Both A and Rare true but R IsNOT a correct explanaton of A.
(c) A is true but R is false.
(d) A is false but R is true.

24. Assertion (A) : The static magnetic field has zero divergence and non-zero curl.
Reason (R) : The static magnetic field satisfies the flux law.

25. Assertion (A) : A glazed ceramic insulator has a lower breakdown strength than an unglazed one.
Reason (R) : Glazing covers pores and cracks and makes the surface non-absorbent.

26. Assertion (A) : In a type II superconductor, the magnetization gradually decreases between two critical values of the applied field Hc1 and Hc2.
Reason (R) : In a type II superconductor, magnetic flux lines are pinned by microstructural imperfection.

27. Assertion (A) : In an alternating field of 1014Hz, the electrical conductivity of a metal is zero.
Reason (R) : As the electrons fail to respond to the fast changing electric field, there is no drift.

28. Assertion (A) Addition of boron to intrinsic or pure silicon in the proportion of one borom atom to
14silicon atoms increases the conductivity of pure silicon by a factor of 10 at room temperature.
Reason (R) : Addition of impurities to intrinsic semiconductors increases carrier mobility

29. Assertion (A) A network consisting of ‘n’ nodes and ‘e’ elements can b_e completely ana1sed from (e — n + 1) mesh equations or (n — 1) node equations.
Reason (R) : The number of mesh equations plus number of node equations is equal to the number of elements in the network.

30. Assertion (A) : The poles and zeros of a rectance function alternate on the s-plane.
Reason (R) : The plot of rectance functions as a function of frequency always has a positive slope.

31. Assertion (A) The state steady response of a linear network is termed ‘forced response’.
Reason (R) : The forcing function does not have any effect on the transient response of a linear system.

32. Assertion (A) A variance is dependent on the mean value of the set of data.
Reason (R) : Variance is the difference of the mean squared values and the square of the mean value of the set of data.

33. Assertion (A) : The vertical deflecting plates of a CRT are kept farther away from the screen as compared to the horizontal deflecting plates.
Reason (R) : This improves accuracy in measurements.

34. Assertion (A) When plant parameter uncertainties are present, the open-loop structure is potentially superior to the closed-loop structure.
Reason (R) : When feedback is employed, there is a possibility of additional noise or uncertainty in the measurement of the plant signals.

35.Consider the following statements:
In electrostatics, the equipotential surface is defined as the surface where
1. Electric field intensity is normal everywhere.
2. Electric field intensity is tangential everywhere.
3. No work is done in moving a charge over it
4. No charge is present
Of these statements
(a) 1 alone is correct
(b) 3 and 4 are correct
(c) 1 and 3 are correct
(d) 2 and 4 are correct

36. Tangential component of the electric field on a perfect conductor will be
(a) infinite
(b) zero
(c) same as the normals field component and 900 out of phase
(d) same as the normal component but 180° out of phase

37. Two conducting shells of radii r1 and r2 (r1 > r2) each with a charge ‘Q’ are placed far apart in uniform external electric field . The space surrounding each shell is filled with the same dielectric material In this situation, the
(a) shells will not experience any force
(b) shells will experience identical forces
(c) shells will radius r1 will experience a greater force
(d) shell with radius r2 will experience a greater force

38. The directivity of an isotropic antenna is
(a) zero
(b) less than unity
(c) unity
(d) infinity

39. Consider the following statements
For a uniform place electromagnetic wave
1. The direction of energy flows the same as the direction of propagation of the wave.
2. Electric and magnetic fields are in time quadrature.
3. Electric and magnetic fields are in space quadrature
Of these statements
(a) 2 alone is correct
(b) 1 and 2 are correct
(c) 1 and 3 are correct
(d) 3 alone is correct

40. For an air dielectric transmission line, it isfound that as the frequency is varies from 50MHz up ward, the current reaches a minimum at 50.01 MHz and then a maximum at 50.04 MHz. The distance of the location of the short-circuit from the generator will then be
(a) 10km
(b) 2.5km
(c) 1 km
(d) not determinable from the given data

Answers:

1 b
2
c
3 c
4 c
5 b
6 b
7 a
8 d
9 a
10 a
11 a
12 c
13 b
14 c
15 a
16 c
17 d
18 a
19 a
20 a
21 d
22 c
23 c
24 b
25 a
26 a
27 a
28 c
29 a
30 a
31 c
32 c
33 a
34 c
35 c
36 b
37 b
38 c
39 c
40 d