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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Q. In carbon resistor colour code, if the third band is of silver, it indicates

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Q. In a metal, the drift velocity of electrons in the presence of a electric field E is

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Q. At a temperature of about 1 K, aluminium is a

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Q. If v is the velocity of electron, tc is the average time between collisions, the mean free path λ = vtc.

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Q. A liquid has N permanent dipoles μᵨ per unit volume and has been subjected to dc field for a long time such that orientation polarization is P₀. At t = 0, the field is suddenly removed, then polarization

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Q. Assertion (A): Orbital magnetic moment of an electron in an atom is of the order of 1 Bohr magneton.

Reason (R): 1 Bohr magneton = 9.27 x 10^-24 A/m².

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Q. As per Bohr's postulate, only those circular orbits are stable for which the angular momentum is equal to an integer times h/2π .

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Q. Inductors used at V.H.F. are made using

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Q. The resistivity of intrinsic semiconductors, at room temperature, is of the order of

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Q. In terms of classical representation of electrons

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Q. To produce magnetic flux, mmf is necessary.

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Q. Semiconductors have a positive temperature coefficient of resistivity.

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Q. An electrolytic capacitor can be used for

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Q. As regards ferromagnetic Curie temperature Qf and paramagnetic curie temperature θ

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Q. The iron core of a coil is removed so that it becomes an air cored coil. Its inductance will

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Q. A circular sphere mile is the area of cross-section of a wire

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Q. In an hydrogen atom, an electron moves in the field of a proton. The stability of orbit requires equilibrium between coulomb's force and centrifugal force.

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Q. For small size high frequency coils, the most common core material is

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