21

A sine wave of voltage varies from zero to
maximum of 200 V. How much is the voltage at the instant of 30° of the cycle ? 100V [other wrong options are – 50V, 82.8V, 173.2 V, ] 
22

The power consumed in a circuit element will be
least when the phase difference between the current and voltage 90° [other wrong options are – 180°, 60°, 0°, ] 
23

The form factor is the ratio of
r.m.s. value to average value [other wrong options are – Peak value to r.m.s. value, Average value to r.m.s. value, None of these, ] 
24

Which of the following is not a nonlinear
element ? Heater coil [other wrong options are – Transistor, Diode, Electric arc with unlike electrodes, ] 
25

At half power points of a resonance curve, the
current is____ times the maximum current. 1/ √2 [other wrong options are – 1/2, √2, 2, ] 
26

The product of apparent power and cosine of the
phase angle between circuit voltage and current is True power [other wrong options are – Reactive power, Voltamperes, Instantaneous power, ] 
27

The power is measured in terms of decibles in
case of Electronic equipment [other wrong options are – Transformers, Current transformers, Autotransformers, ] 
28

The safest value of current the human body can
carry for more than 3 second is 9 mA [other wrong options are – 4 mA, 15 mA, 25 mA, ] 
29

The power factor at resonance in RLC parallel
circuit is Unity [other wrong options are – Zero, 0.08 Lagging, 0.8 Leading, ] 
30

Capacitors for power factor correction are rated
in kVAR [other wrong options are – kW, kVA, kV, ] 
31

For 200 V r.m.s. value triangular wave, the peak
voltage will be 346 V [other wrong options are – 200 V, 222 V, 282 V, ] 
32

Two waves of the same frequency have opposite
phase when the phase angle between them is 180° [other wrong options are – 360°, 90°, 0°, ] 
33

A network is said to be nonlinear if it does not
satisfy Both (A) and (B) [other wrong options are – Homogeneity condition, Superposition condition, Associative condition, ] 
34

The value of operator j2 is equal to
1 [other wrong options are – Zero, +1, √1, ] 
35

The power factor of a D.C. circuit is always
Unity [other wrong options are – Less than unity, Greater than Unity, Zero, ] 
36

At____ frequencies the parallel RL circuit
behaves as purely resistive. Very high [other wrong options are – Low, Very low, High, ] 
37

If resistance is 20 ω and inductance is 2H in a
RL series circuit, then time constant of this circuit will be 0.1 S [other wrong options are – 0.001 S, 10 S, 100 S, ] 
38

The transient currents are associated with the
Changes in the stored energy in the inductors and capacitors [other wrong options are – Impedance of the current, Applied voltage to the circuit, Resistance of the circuit, ] 
39

The best place to install a capacitor is
Across the terminals of the inductive load [other wrong options are – Very near to inductive load, Far away from the inductive load, Any where, ] 
40

For a sine wave with peak value Emax
the average value is 0.636 Emax [other wrong options are – 0.707 Emax, 0.434 Emax, 1.414 Emax, ] 