Q. To protect the diodes in a rectifier and capacitor input filter circuit it is necessary to use

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Q. Maximum efficiency of class B power amplifier is 50%.

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Q. The self bias provides

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Q. The efficiency of a full wave rectifier using centre tapped transformer is twice that in full wave bridge rectifier.

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Q. Assertion (A): CE amplifier is the most widely used BJT amplifier

Reason (R): CE amplifier has zero phase difference between input and output

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Q. Assertion (A): For large signal variations an amplifier circuit has to be analysed graphically

Reason (R): The output characteristics of a transistor is nonlinear.

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Q. Negative feedback reduces noise originating at the amplifier input.

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Q. An RC coupled amplifier has an open loop gain of 200 and a lower cutoff frequency of 50 Hz. If negative feedback with β = 0.1 is used, the lower cut off frequency will be

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Q. The load impedance ZL of a CE amplifier has R and L in series. The phase difference between output and input will be

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Q. If an amplifier with gain of - 1000 and feedback factor β = - 0.1 had a gain change of 20% due to temperature, the change in gain of the feedback amplifier would be

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Q. Which of the following power amplifiers has highest efficiency?

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Q. A full wave rectifier using centre tapped transformer and a bridge rectifier use similar diodes and have equal no load output voltage. Under equal load conditions

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Q. In an amplifier with a gain of - 1000 and feedback factor β = - 0.1, the change in gain is 20% due to temperature. The change in gain for feedback amplifier will be

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Q. The open loop gain of an amplifier is 200. If negative feedback with β = 0.2 is used, the closed loop gain will be

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Q. In a class C power amplifier the input signal has a frequency of 250 kHz. If the collector current pulses are 0.1 μs wide, the duty cycle of current waveform is

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Q. The dissipation at the collector is in the quiescent state and increases with excitation in the case of a

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Q. The open loop gain of an ideal op-amp is

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Q. The ideal characteristics of a stabilizer is

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Q. A difference amplifier using op-amp has closed loop gain = 50. If input is 2 V to each of inverting and non-inverting terminals, output is 5 mA. Then CMRR =

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Q. The coupling capacitor in amplifier circuits

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