MCQ
1721. What quantity of charage must be delivered by a battery with a potential difference of 100 V to do 500) of work?
5C
50C
0.5C
500C
1722. Pure inductive circuit-
Consumes some power on average
Does not take power at all from a line
Takes power from the line during some parts of the cycle and then returns back to it during
other parts of the cycle None of the above
1723. Magnitude of current at resonance in R-L-C circuit-
Depends upon the magnitude of R
Depends upon the magnitude of L
Depends upon the magnitude of C
Depends upon the magnitude of R, L and C
1724. What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value and the other is at zero value?
45°
90°
180°
30°
1725. In an AC circuit, a low value of KVAR compared with kW indicates-
Low efficiency
High-power factor
Unity power factor
Maximum load current
1726. The double energy transient occur in the-
R-L circuit
R-C circuit
R-L-C circuit
Purely inductive circuit
1727. Which of the following statements pertains to resistors only?
Can dissipate considerable amount of power
Can act as energy storage devices
Connecting them in parallel increases the total value
Oppose sudden changes in voltage
1728. Capacitive reactance is more, when-
Capacitance is less and frequency of supply is less
Capacitance is less and frequency of supply is more
Capacitance is more and frequency of supply is less
Capacitance is more and frequency of supply is more
1729. A capacitor opposes---
charge in current
charge in voltage
both charge in current and voltage
none
1730. --- Power factor of the following circuit will be zeгo.
Resistance
Inductance
Capacitance
Both (b) and (c)
1731. An air-core choke coil and an electric bulb are connected in series with ac mains. On introducing soft iron bar in the coil, the intensity of light will-
fluctuate
remain unchanged
increase
decrease
1732. In a highly capacitive circuit, the-
Apparent power is equal to the actual power
Reactive power is more than the apparent power
Reactive power is more than the actual power
Actual power is more than its reactive power
1733. The capacitance of a capacitor is influented by-
Plate thickness
Plate separation
Plate area
Both (b) and (c)
1734. Which resistor will be physically larger in size-
10Ω 50W
100Ω 10W
1ΜΩ 1W
1KΩ 1W
1735. The safest value of current the human body can carry for more than 3 second is-
4mA
9mA
15mA
25mA
1736. The purpose of a parallel circuit resonance is to magnify-
Current
Voltage
Power
Frequency
1737. One watt-hour is equal to-
360 Joule
300 Joule
3000 Joule
3600 Joule
1738. Pure inductive circuit takes power from the A.C. line, when-
Applied voltage decreases but current increases
Applied voltage increases but current decreases
Both applied voltage and current increase
Both applied voltage and current decrease
1739. In any A.C. circuit always-
Apparent power is more than actual power
Reactive power is more than apparent power
Actual power is more than reactive power
Reactive power is more than actual power
1740. How long does it take 50 µC of charge to pass a point in a circuit if the current flow is 15 mA?
3.33 x 10^3s
6 x 10^3s
6.33 × 10^3s
2s