 
			 
			MCQOPTIONS
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				This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Power Electronics knowledge and support exam preparation. Choose a topic below to get started.
| 1. | A single-phase half-wave thyristor circuit with R load is triggered at an angle of α = 0°. As such, the maximum value of the average output voltage would be given byConsider Vs = Vm sinωt. | 
| A. | Vm | 
| B. | 2Vm/π | 
| C. | Vm/π | 
| D. | Vm/α | 
| Answer» D. Vm/α | |
| 2. | For the below given circuit with firing angle α & angular frequency of ω, the circuit turn-off time in secs can be given by | 
| A. | α/π | 
| B. | π/α | 
| C. | ω/π | 
| D. | π/ω | 
| Answer» E. | |
| 3. | For a single phase thyristor circuit with R load & firing angle α, the conduction angle can be given by | 
| A. | π+α | 
| B. | 2π+α | 
| C. | π-α | 
| D. | α | 
| Answer» D. α | |
| 4. | Below shown ideal circuit is triggered at a firing angle of α. From ωt = π to 2π+α | 
| A. | SCR voltage is zero | 
| B. | Load voltage is maximum | 
| C. | SCR voltage is –Vmsinα | 
| D. | SCR acts like a short circuit | 
| Answer» D. SCR acts like a short circuit | |
| 5. | Below shown ideal circuit is triggered at a firing angle of α. The voltage across the SCR is zero from ωt = | 
| A. | 0 to α | 
| B. | 0 to π | 
| C. | α to 2π | 
| D. | α to π | 
| Answer» E. | |
| 6. | In a single phase half-wave thyristor circuit with R load & Vs=Vm sinωt, the maximum value of the load current can be given by | 
| A. | 2Vm/R | 
| B. | Vs/R | 
| C. | Vm/2 | 
| D. | Vs/2 | 
| Answer» D. Vs/2 | |
| 7. | In the method of phase control, the phase relationship between ___ & ___ is controlled by varying the firing angle | 
| A. | supply current, supply voltage | 
| B. | end of the load current, end of the load voltage | 
| C. | start of the load current, start of the load voltage | 
| D. | load current, load voltage | 
| Answer» D. load current, load voltage | |
| 8. | In the below given circuit, the SCR is triggered at a certain firing angle α.The load current falls to zero at ωt = | 
| A. | α | 
| B. | α/2 | 
| C. | π | 
| D. | π/2 | 
| Answer» D. π/2 | |
| 9. | The average output voltage is maximum when SCR is triggered at ωt = | 
| A. | π | 
| B. | 0 | 
| C. | π/2 | 
| D. | π/4 | 
| Answer» C. π/2 | |
| 10. | A voltage source Vs = Vm sinωt is connected in series with a resistance R and an SCR. At some firing angle delay of α a positive gate pulse is applied to the SCR which turns on the SCR. Considering ideal conditions, at the instant α the voltage at the resistor terminals Vo | 
| A. | falls to zero | 
| B. | falls to –Vm sin α | 
| C. | rises to Vm sin α | 
| D. | rises to Vm sin ωt | 
| Answer» D. rises to Vm sin ωt | |