Computer Programming MCQs

5739 MCQs  (Page 133 of 574)

Power factor of the following circuit will be zero__________?
A. Resistance
B. Inductance
C. Capacitance
D. Both b. and c.
Power factor of the system is kept high__________?
A. To reduce line losses
B. To maximise the utilization of the capacities of generators, lines and transformers
C. To reduce voltage regulation of the line
D. Due to all above reasons
In a loss-free R-L-C circuit the transient current is__________?
A. Oscillating
B. Square wave
C. Sinusoidal
D. Non-oscillating
The square waveform of current has following relation between r.m.s. value and average value?
A. R.m.s. value is equal to average value
B. R.m.s. value of current is greater than average value
C. R.m.s. value of current is less than average value
D. None of the above
The time constant of the capacitance circuit is defined as the time during which voltage________?
A. Falls to 36.8% of its final steady value
B. Rises to 38.6% of its final steady value
C. Rises to 63.2% of its final steady value
D. None of the above
The r.m.s. value of alternating current is given by steady (D.C.) current which when flowing through a given circuit for a given time produces__________?
A. The more heat than produced by a.c. when flowing through the same circuit
B. The same heat as produced by a.c. when flowing through the same circuit
C. The less heat than produced by a.c. flowing through the same circuit
D. None of the above
In a pure resistive circuit__________?
A. Current lags behind the voltage by 90°
B. Current leads the voltage by 90°
C. Current can lead or lag the voltage by 90°
D. Current is in phase with the voltage
The transient currents are associated with the____________?
A. Changes in the stored energy in the inductors and capacitors
B. Impedance of the circuit
C. Applied voltage to the circuit
D. Resistance of the circuit
In the case of an unsymmetrical alternating current the average value must always be taken over__________?
A. Unsymmetrical part of the wave form
B. The quarter cycle
C. The half cycle
D. The whole cycle