36. Excessive hum in a power supply could be due to
A. open filter choke
B. capacitor
C. defective rectifier
D. any of the above
37. The rms ripple voltage is 20 mV for a 15 V dc output. The percentage ripple factor will be
A.0.01%
B.0.07%
C.0.13%
D.1.30%
38. The dc output voltage is 40 V at full load and 41 V without any load current. The load regulation is
A.0.24%
B.0.48%
C.0.96%
D.2.40%
39. The gate is -5 V and the anode voltage is 500 V. It can be concluded that SCR is
A. ON at full load
B. ON at part load
C. ON at no load
D. OFF
40. For a SCR typical gate trigger voltage is
A. 0.2 V
B. 6 V
C. 60 V
D. 600 V
41. The voltage drop across a triac in conduction is about
A. 1 gV
B. 1 mV
C. 1 mV
D. 100 V
42. The voltage drop across a SCR in conduction state is about
A. 100 V
B. 1 V
C. 30 V
D. 1 gV
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