1. Arc heating occurs when the air between electrodes of opposite polarity becomes :
2. The meter used to measure the temperature of a furnace is :
3. Which part is provided in a battery charger to prevent the flow of excessive current into the battery?
4. What are the two relative quantities to be DC shunt generator?plottedfor external characteristics curve for
5. What will happen to a self excited DC generator, if the generator runs in reverse direction?
6. The colour of light of mercury vapour lamp is :
7. Which of the following frequencies has the longest lime period?
8. In a generator maximum value of e.m.f. is generated within the coil axis is at:
9. A choke coil of an operating fluorescent lamp is short-circuited. What is the consequence?
10. A contactor coil is designed for 220V DC. What happens if it is connected to 220 V AC?
11. A capacitor is connected across a 200 V AC line. Its minimum voltage rating should be :
12. The power factor of 3-phase load is less than 0.5. While measuring power by two watt meters :
13. Voltage required to operate the Neon sign tubes depends upon :
14. Soldering of a Britannia joint is a necessity to avoid loosening of the joint due to :
15. Braking torque in energy meter is produced to :
16. The standard secondary voltage for a PT used in power system in :
17. Which instrument always indicates true r.m.s. value irrespective of the waveform?
18. A voltmeter gives inaccurate reading to measure the drop across a low resistance because :
19. The phase difference between the currents in the two pressure coils in PF meter is :
20. When a rewound armature is rolled on the surface of a leveled surface plate the armature stops at the same position of its periphery for each rolling, the portion of armature touching the surface plate is regarded to have :
21. Which one of the follow ing characteristic is NOT applicable to synchronous motors?
22. The colour of light depends upon :
23. Which of the following lamp is a cold cathode lamp?
24. You have to repair storage type water heater which has steam in the hot water. The possible remedy for this trouble can be found by checking :
25. The reading on a 3 digit millivoltmeter started flashing continuously when connected across a resistor to measure the mV across it. The reason for flashing of display on millivoltmeter is that: