Q. The turn on characteristics of a power transistor can be assumed to be linear, as shown in the below figure . During turn on time T, voltage reduces linearly from V to 0 and current rises linearly from 0 to I. The energy loss during time T is

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Q. The circuit in figure is for

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Q. If 0.5 T is the time period of oscillations and Toff is the time between turn off of one thyristor and turn on of second thyristor, the frequency of output f of a series inverter is

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Q. In auxiliary commutated chopper fed by voltage V and having L and C commutating elements, the peak value of capacitor current is

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Q. A single phase half wave converter is feeding-a resistor load. The input voltage is v = Vm sin ωt. If firing angle is zero, the output dc voltage Vdc and output rms voltage Vrms respectively

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Q. A single phase converter is fed by a source having an inductance L. If load current is I₀, the decrease in output voltage due to overlap is

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Q. In a full bridge inverter fed by a battery of voltage V, the rms value of fundamental component of output voltage is

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Q. Two single phase semi-converters are connected in series to form a series converter. The input is v = Vm sin ωt and α1, α2 are the firing angles. If α1 = 0, the dc output voltage is

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Q. A capacitor C farads is charged to a voltage V. It discharges through a thyristor, a diode and an inductance L. The peak current in the circuit is

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Q. A dc chopper feeds an RLE load and has a duty cycle of 1. The load current will be such that

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Q. In a half bridge inverter circuit fed by a battery of voltage V, the rms value of fundamental component of output voltage is

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Q. The symbol in figure is for

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Q. In a parallel inverter the turn off time tq of thyristor and values of commutating elements L and C are related as

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Q. The symbol in figure is for

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Q. If peak value of input voltage is Vm and firing angle is α, the average output voltage for single phase half wave and single phase full wave regulators are

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Q. Assertion (A): The circuit of figure thyristor will conduct for 180° during positive half cycle if it is continuously fired.

Reason (R): A thyristor can conduct only when it is forward biased.

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Q. In the below figure, the load is highly inductive. The firing angle is a for each of the thyristors. The periods of conduction of Th1 and Th2 respectively are

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Q. The condition for underdamped oscillations in a series RLC circuit is

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Q. A single phase fully controlled bridge converter is fed by a voltage Vm sin ωt. The average and rms values of output voltage are

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Q. Which of the following is correct for a BJT?

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