1. The permissible flux density of cold rolled grain oriented steel used for transformer core is around :
2. The nameplate of an energy meter reads 1 KWh = 15,000 revolutions’. If the meter completes 150 revolutions during 50 seconds, what is the power in the circuit?
3. An ammeter with full scale deflection current of 100 A (micro ampere) and internal resistance of 100 is required to measure a maximum current of 10 maA. The shunt resistance value is:
4. If the moving coil of a voltmeter consists of 100 turns around on a square former which has a length of 30 mm and flux density in the air gap is 0.09 wb/m2. The deflecting torque on the coil when carrying a current of 10 mA is :
5. A 5 A. 230 V meter on full load, unity power factor test makes 72 revolutions in 360 seconds If the normal disc speed is 600 rev/KWh, what is the percentage error?
6. In a moving iron instrument, the deflection torque, Td is :
7. Inductance affects the direct current (d.c.) flow :
8. For a sine wave with peak value Emax, the average value is :
9. The ratio of starting torque to full load torque is least in :
10. The iron core from an iron-cored coil is removed so that it becomes air-cored. The inductance of the coil:
11. The forbidden energy band gap for Germanium is :
12. When the reverse bias is applied to a junction diode :
13. In a full-wave rectifier which uses two ideal diodes, the approximate relationship are :
14. Which of the following statement is correct for the basic transistor configurations?
15. A Bipolar Junction transistor is said to bo operating in saturation region if
16. Pinch - off voltage of a JFET is :
17. The best material for the gate region construction of a MOSFET is :
18. The common-emitter short circuit current gain p of a BJT :
19. For full-wave rectification, a four-diode bridge rectifier is claimed to have the following advantages over a two-diode circuit:(1) Less expensive transformer (2) Smaller size transformer and (3) Suitability for higher voltage application Of these
20. A 1 MHz sinusoidal carrier wave is amplitude modulated by a sine wave of period 100 μs. Which of the following frequencies will not be present in the modulated output signal?(A) 990 KHz (B) 1000 KHz(C ) 1010 KHz (D) 1020 KHz
21. The image frequency of the AM super heterodyne i receiver when it is tuned to receive a radiostation operating at 628 KHz is :
22. A 741 type op-amp has a gain bandwidth product of 1 1 MHz. A non-inverting amplifier usingthis op-amp and having a voltage gain of 20 dB will exhibit a -3dB bandwidth of:
23. How many number of NOR gates are required to realise an AND function?
24. Simplified form of the logic expression : (X + Y + Z)(X + Y¯ + Z) (X +¯Y-¯Z)