MCQ
4641. --- Power factor of the following circuit will be zeгo.
Resistance
Inductance
Capacitance
Both (b) and (c)
4642. 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
4643. Skin effect occurs when a conductor carries current at frequencies,
low
High
Very low
Medium
4644. 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
4645. In a loss-free R-L-C circuit, the transient current is-
Oscillating
Square wave
Sinusoidal
Non-oscillating
Himalay Sen Sir
ইলেক্ট্রিক্যাল ডিপার্টমেন্ট Mcq
EEE MCQ
Electrical Department all question
এসি সার্কিট MCQ ALL
AC Circuit mcq
ব্যাখ্যা: ব্যাখ্যা: The circuit is losa-free, therefore there will be no effect of resistance and components: Land C. The transient 2 current will be sinusoidal in nature.
4646. The safest value of current the human body can carry for more than 3 second is-
4mA
9mA
15mA
25mA
4647. The frequency of domestic power supply in Bangladesh is --
200Hz
60Hz
100Hz
50Hz
4648. 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°
4649. 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
4650. 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
4651. 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
4652. 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
4653. The frequency of an alternating current is-
The speed with which the alternator runs
The number of cycles generated in one minute
The number of waves passing through a point in one second
The number of electrons passing through a point in one second
4654. In an AC circuit, a low value of KVAR compared with kW indicates-
Low efficiency
High-power factor
Unity power factor
Maximum load current
4655. 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
4656. The double energy transient occur in the-
R-L circuit
R-C circuit
R-L-C circuit
Purely inductive circuit
4657. 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
4658. Time constant of a capacitive circuit-
Increases with the decrease of capacitance and decrease of resistance
Increases with the decrease of capacitance and increase of resistance
Increases with the increase of capacitance and 2 decrease of resistance
Increases with the increase of capacitance and the increase of resistance
4659. In a pure inductive circuit if the supply frequency is reduced to 1/2, the current will-
Be reduced by half
Be doubled
Be four times as high
Be reduced to one fourth
4660. The purpose of a parallel circuit resonance is to magnify-
Current
Voltage
Power
Frequency