AP TRANSCO QUESTION PAPER

Electrical Circuits and Networks:

1. The ratio of voltage and electric current in a closed circuit
   (a) remains constant (b) varies (c) increases (d) falls
2. The resistance of a wire varies inversely as
   (a) area of cross section (b) length (c) resistivity (d) temperature
3. The electrical conductivity of metals is typically of the order of ( in ohm-1 m-1)
   (a) 10 to the power of 7 (b) 10 to the power of 5 (c) 10 to the power of -4 (d) 10 to the power of -6
4. Four resistors, each of resistance R ohms are available. The minimum resistance of the combination will be
   (a) 4R (b) R (c) R/4 (d) R/8
5. The elements which are not capable of delivering energy by its own are known as
   (a) unilateral elements (b) non-linear elements (c) passive elements (d) active elements
6. The magentic susceptibility of paramagnetic material is
   (a) less than zero (b) less than one but positive (c) greater than one (d) equal to zero
7. The Direction of current in an ac circuit
   (a) is from positive to negative (b) is always in one direction (c) varies from instant to instant (d)Cannot be determined
8. which of the following statements associated with purely resistive circuits is correct?
   (a) PF is unity (b) Power consumed is zero (c) Heat produced is zero (d) PF is zero
9. The magnetic field energy in an inductor changes from maximum value to minimum value in in 5m sec when connected to an ac source. The frequency of the source is
   (a) 20 Hz (b) 50 Hz (c) 200 Hz (d) 500 Hz
10. 
    

Control Systems:

1. Electronic control systems have the serious draw-backs of
   (a) low reliability (b) operational difficulty (c) temperature sensitiveness (d) all of above
2. The system whose characteristic equation has the following roots is marginally stable
   (a) -j, j, -1,1 (b) -3,-2,0 (c) -2+3j, -2-3j, -2 (d) -3,-2,-1
3. A phase log compensation will
   (a) improve relative stability
   (b)increase the speed of response
   (c)increase band-width
   (d) increase overshoot
4. For Nyquist plot we use

1. open loop function
2. closed loop function
3. characteristic equation
4. any of the above

A system with gain margin close to unity or a phase margin close to zero is

1. highly stable
2. oscillatory
3. relatively stable
4. none of these

Root locus diagram exhibits the

1. frequency response of a system
2. poles of the transfer function for a set of parameter values
3. bandwidth of system
4. all of the above

Increase in the gain K makes the system

1. more stable
2. unstable
3. none of above

The transfer function of a system is used to determine

1. the output for a given input
2. the type of system
3. the input for a given output
4. the steady state gain

In a servo system the voltage induced in the control transformer rotor is the

1. error voltage
2. driving voltage
3. opposing voltage
4. none of these

With the feedback system, the transient response

1. decays slowly
2. decays rapidly
3. rises slowly
4. rises quickly

Measurements and Instrumentation

1. Which of the following types of instrument is an integrating instrument?

1. power factor meter
2. energy meter
3. wattmeter
4. frequent meter

Which of the material is used for the ’swamping’ resistance that is connected in series with the working coil of a voltmeter?

1. Constantan
2. Manganin
3. Eureka
4. Nichrome

What are used to increase the range of ammeters.

1. Multipliers
2. Shunts
3. Control Springs
4. Potential transformers

Which voltmeter do you select for measuring 50KV DC?

1. Moving Coil Voltmeter
2. Hot wire voltmeter
3. Electro Dynamo meter
4. Electrostatic Voltmeter

Which of the following you will prefer to extend the range of an ac voltmeter?

1. Low series resistance
2. high resistance in parallel
3. CT
4. PT

High AC voltages are usually measured with

1. magnetic voltmeter
2. inductive voltmeter
3. potential transformers with voltmeters
4. current transformers and voltmeters

Creeping is the phenomena occurs in

1. voltmeter
2. wattmeter
3. energy meter
4. ammeter