250+ TOP MCQs on Fullwave Rectifier and Answers

Analog Circuits Multiple Choice Questions on “Fullwave Rectifier”.

1. DC average current of a center taped full wave rectifier is _______________
(Where I_m is the maximum peak current of input)
A. 2I_m/ᴨ
B. I_m/ᴨ
C. I_m/2ᴨ
D. 1.414I_m/ᴨ
Answer: A
Clarification: Average DC current is the average current in the output of the rectifier. For a center tapped full wave rectifier, if a sinusoidal input is given, then output will contain only one half cycle repeatedly. So average current will be twice as half wave rectifier.

2. DC power output of center tapped full wave rectifier is equal to ___________
(I_m is the peak current and R_L is the load resistance)
A. (2I_m²/ᴨ²)R_L
B. (I_m²/2 ᴨ²)R_L
C. (I_m²/ᴨ²)R_L
D. (4I_m²/ᴨ²)R_L
Answer: D
Clarification: DC output power is the power output of the rectifier. It is equal to V_DCI_DC.
We know V_DC for a center taped rectifier is 2V_m/ᴨ and I_DC for a center tap rectifier is 2I_m/ᴨ.
We also know V_DC = I_DC/R_L.
Hence output power is (4I_m²/ ᴨ²)R_L.

3. Ripple factor of center tapped full wave rectifier is _____________
A. 1.414
B. 1.21
C. 1.3
D. 0.48
Answer: D
Clarification: Ripple factor of a rectifier is the measure of the effectiveness of a power supply filter in reducing the ripple voltage. It is calculated by taking a ratio of RMS AC voltage to DC output voltage. For a center tapped full wave rectifier, it is 0.482.

4. If input frequency is 50Hz then ripple frequency of center tapped full wave rectifier will be equal to _____________
A. 100Hz
B. 50Hz
C. 25Hz
D. 500Hz
Answer: A
Clarification: Since in the output of center tapped rectifier one half cycle is repeated hence frequency will twice as that of input frequency. That is 100Hz.

5. Transformer utilization factor of a center tapped full wave rectifier is equal to ___________
A. 0.623
B. 0.678
C. 0.693
D. 0.625
Answer: C
Clarification: Transformer utilization factor is the ratio of DC power supplied to the AC rating of the primary winding. The factor indicated the effectiveness of transformer usage by the rectifier. For a center tapped full wave rectifier, it is equal to 0.81 w.r.t the primary winding, 0.57 w.r.t the secondary winding (double of that of a half wave rectifier) and the average value is 0.69.

6. If peak voltage on a center tapped full wave rectifier circuit is 5V and diode cut-in voltage is 0.7, then peak inverse voltage on diode will be ___________
A. 4.3 V
B. 10 V
C. 5.7 V
D. 9.3 V
Answer: B
Clarification: PIV is the maximum reveres bias voltage that can be appeared across a diode in the circuit. If PIV rating of the diode is less than this value breakdown of diode may occur. For a center tapped full wave rectifier, PIV of diode is 2V_m. Therefore, PIV is 10 V.

7. Efficiency of center tapped full wave rectifier is ___________
A. 50%
B. 81.2%
C. 40.6%
D. 45.3%
Answer: B
Clarification: Efficiency of a rectifier is the effectiveness of rectifier to convert AC to DC. It is obtained by taking a ratio of DC power output to maximum input power delivered to load. It is usually expressed in percentage. For center tapped full wave rectifier, it is 81.2%.

8. In a center tapped full wave rectifier, the input sine wave is 20sin500 ᴨt. The average output voltage is __________
A. 12.73V
B. 6.93V
C. 11.62V
D. 3.23V
Answer: A
Clarification: The equation of sine wave is in the form E_m sin wt.
Therefore, E_m=20
Hence output voltage is 2E_m/ ᴨ. That is 40/ ᴨ.

9. In a center tapped full wave rectifier, the input sine wave is 200sin50 ᴨt. If load resistance is of 1k then average DC power output of half wave rectifier is __________
A. 12.56W
B. 16.20W
C. 4.02W
D. 8.04W
Answer: B
Clarification: The equation of sine wave is in the form E_m sin wt.
On comparing E_m = 200
Power = 4E_m2/ ᴨ²R_L = 800/ ᴨ²x 1000 = 16.20W.

10. In a center tapped full wave rectifier, the input sine wave is 250sin100 ᴨt. The output ripple frequency of rectifier will be __________
A. 50Hz
B. 200Hz
C. 100Hz
D. 25Hz
Answer: C
Clarification: The equation of sine wave is in the form E_m sin wt.
Therefore, w = 100ᴨ that is, frequency f = w/2ᴨ = 50Hz
Since the output of center tapped full wave rectifier have double the frequency of input, output frequency is 100Hz.