Overhead lines for power supply to tramcars are at a minimum height of______________?

Related Mcqs:

1. The return circuit for tramcars is through_______________?

   A. neutral wire
   B. rails
   C. cables
   D. common earthing

2. The maximum a.c. power output from a class A power amplifier is 10 W. What should be the minimum power rating of the transistor used ?

   A. 10 W
   B. 15 W
   C. 5 W
   D. 20 W

3. For the same a.c. power output as above, what should be the minimum power rating of transistor for class B operation?

   A. 10 W
   B. 4 W
   C. 8 W
   D. None of the above

4. The class B push-pull circuit can deliver 100 W of a.c. output power. What should be the minimum power rating of each transistor ?

   A. 20 W
   B. 40 W
   C. 10 W
   D. 80 W

5. What will be the collector efficiency of a power amplifier having zero signal power dissipation of 5 watts and a.c. power output of 2 watts ?

   A. 20%
   B. 80%
   C. 40%
   D. 50%

6. The output power of a transistor amplifier is more than the input power because the additional power is supplied by__________________?

   A. Transistor
   B. Biasing circuit
   C. Collector supply VCC
   D. None of the above

7. For 25 kV single phase system power supply frequency is_______________?

   A. 60 Hz
   B. 50 Hz
   C. 25 Hz
   D. 16 Hz

8. The rate of acceleration on suburban orurban services is restricted by the consideration of______________?

   A. Engine power
   B. Track curves
   C. Passenger Discomfort
   D. Track size

9. An amplifier receives 0.1 W of input signal and delivers 15 W of signal power. What is the power gain in db?

   A. 8 db
   B. 6 db
   C. 5 db
   D. 4 db

10. The power output of an audio system is 18 W. For a person to notice an increase in the output (loudness or sound intensity) of the system, what must the output power be increased to ?

    A. 2 W
    B. 6 W
    C. 68 W
    D. None of the above