Q. Electrical contact materials used in switches, brushes and relays must possess

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Q. A JFET behaves as a constant current source when

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Q. The electron and hole concentration in a intrinsic semiconductor are ni and Pi respectively when doped with a P type material, these change to n and P, respectively. Then

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Q. The energy to cause thermionic emission is supplied by heating the cathode.

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Q. Assertion (A): In an n-p-n transistor as the electrons enter the collector region, they are accelerated towards the collector terminal.

Reason (R): Emitter base junction in BJT is forward biased.

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Q. Assertion (A): In reverse biased p-n junction, the reverse saturation current is nearly constant if the reverse voltage is less than critical value.

Reason (R): The total reverse current is sum of reverse saturation current and surface leakage current.

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Q. The mass of an electron is nearly

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Q. The cut in voltage

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Q. With an ac input from 50 Hz power line, the ripple frequency is

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Q. For an insulating material, dielectric strength and dielectric loss should be respectively

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Q. Semiconductors have

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Q. The I/P impedance (Zi) and the O/P impedance (Zo) of an ideal trans conductance (Voltage controlled current source) amplifier are

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Q. The relation between thermionic emission current and temperature is known as

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Q. Assertion (A): When forward biased a p-n junction has low resistance.

Reason (R): The ratio dv/di is called dynamic resistance.

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Q. Assertion (A): JFET is a voltage controlled device.

Reason (R): The drain current can be controlled by controlling VGS.

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Q. For a P-N junction diode, the current in reverse bias may be

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Q. An amplifier with resistive -ve feedback has two left poles in its open loop transfer function. The amplifier

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Q. Amplification of ultrasonic waves is possible in a piezoelectric semiconductor under applied electric field. The basic phenomenon involved is known as

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Q. For a junction FET in the pinch off region, as the drain voltage is increased, the drain current

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Q. For a BJT, under the saturation region.

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