Q. Assertion (A): Acceptor extrinsic semiconductor has higher conductivity than intrinsic semiconductor.

Reason (R): Addition of p-type impurity produces an allowable discrete energy level just above valence band.

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Q. When temperature is above ferromagnetic Curie temperature, a ferromagnetic material

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Q. A magnet does not attract

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Q. Bitter powder patterns prove the existence of domains.

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Q. Assertion (A): An amorphous material is obtained when mobility of atoms is inhibited during solidification.

Reason (R): Crystalline state is a natural state for most solids.

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Q. An air cored inductance is a

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Q. The number of valence electrons in silicon atom is

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Q. ∈ᵣ is determined by the atomic structure of the dielectric.

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Q. A rare gas has N atoms per m³. If electronic polarizability of single atom of this gas is αe, then

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Q. The colour code on a carbon resistor is brown-black-red-gold. The value of resistance is

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Q. M = (μᵣ - 1)H.

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Q. Silicon and germanium are elements in the

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Q. A sample of N type semiconductor has an electron density of 6.25 x 10¹⁸/cm³ at 300 K. If intrinsic concentration of carriers in this sample is 2.5 x 10¹³/cm³ at this temperature, the hole density is

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Q. Assertion (A): In a conductor, current density remains constant in time as long as E is constant.

Reason (R): In a conductor, J = σE.

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Q. Hysteresis curve is associated with motion of domain walls.

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Q. The number of protons in germanium atom is

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Q. Sulphur hexafluoride is used in

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Q. The number of valence electrons in trivalent impurity is

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Q. Soft iron is suitable for making temporary magnets.

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Q. Antiferromagnetic materials do not have permanent dipoles.

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