Q. The class of insulation of impregnated paper is

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Q. Assertion (A): The resistance of a copper specimen changes by about 22% when temperature is increased from room temperature to 700°C.

Reason (R): The physical properties of a material are determined mostly by the extent of impurities.

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Q. Resistivity of rubber is about

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Q. An iron specimen has µᵣ = 1000 when B = 0.3 T. If B = 0.35 T, µᵣ

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Q. Which solid dielectric has highest temperature limit?

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Q. Permeability is analogous to

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Q. The colour code on a carbon resistor is green-blue-yellow. The tolerance is

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Q. At a very low temperature, a semiconductor

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Q. The colour code on a carbon resistor is red-red-black-silver. The value of resistor is

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Q. Some typical examples of macroscopic quantities are

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Q. The temperature coefficient of a thermistor

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Q. Assertion (A): Helium, Argon and Neon are gaseous at room temperature.

Reason (R): The atoms in Helium, Argon and Neon are chemically extremely inactive.

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Q. Assertion (A): For most metals, Fermi energy EF is less than 10 eV.

Reason (R): Fermi level of a metal is given by EF = 3.64 x 10^-19 (n)^2/3 where n is number of free electrons/m³ of metal.

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Q. The capacitance of an insulated conducting sphere of radius R in vacuum is

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Q. The transition of electron from energy level W1 to W2 is associated with emission or absorption of electro magnetic radiation of frequency f such that

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Q. Even at room temperature, an intrinsic semiconductor has some holes. These holes are due to

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Q. If a capacitor C having selectivity factor Q is scaled down in all its dimensions by a factor K without any altering the dielectric material, the new capacitor will have capacitance and selectivity as

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Q. The hysteresis loss is

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Q. Assertion (A): For a magnetic material M = (μᵣ - 1) H, where M is magnetic dipole moment/m³, H is field intensity A/m and μᵣ is relative permeability.

Reason (R): μᵣ can have any value from 0 to hundreds of thousands.

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Q. As regards ∈₀ and ∈ᵣ (absolute and relative permittivity)

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