Q. Magnetic hysteresis phenomenon is explained by

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Q. The relation between thermal conductivity K (W/m/°C), heat flow density Q (watt/m²) and dT/dx (°C per metre) is

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Q. Assertion (A): The equation D = ∈₀∈ᵣE is applicable only to isotropic materials.

Reason (R): In polycrystalline materials, the directional effects are absent.

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Q. Assertion (A): For a dielectric, P = ∈₀(∈ᵣ - 1) E.

Reason (R): Dipole moment per unit volume is called polarization of dielectric.

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Q. Assertion (A): Ferrites are very useful at very high frequencies.

Reason (R): Ferrites have high permeability and high resistivity.

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Q. In a conductor the current flow is due to

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Q. When an electron moves at velocity v in combined electric and magnetic fields E and H, the Lorentz force F is F = - e(E + v x B).

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Q. When Schrodinger equation is applied to the motion of electron in the field of protons, the physically acceptable solutions for the wave function exist for quantum number which are

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Q. For dielectrics in alternating field, polarizability αe is a complex quantity. The imaginary part of ae is zero for

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Q. In the wave mechanical theory, the maximum of the charge distribution in the ground state occurs for a distance from the nucleus equal to

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Q. The induced magnetic dipole moment has a direction opposite to the applied magnetic field.

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Q. An atom of polarizability a is placed in a homogeneous electric field E. The energy stored in polarized atom is

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Q. If B, H and M denote flux density, field intensity and magnetisation, B = μ₀ (H + M).

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Q. A capacitor can be represented by a capacitance and resistance in parallel. For a good capacitor, this parallel resistance should be

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Q. Assertion (A): Ionic solids, in general, have no electrical conductivity.

Reason (R): In ionic solids, electrons are tightly bound to the nucleus.

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Q. Tesla is a unit of

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Q. If the operating temperature increases by 10°C, the rate of deterioration of solid dielectric becomes

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Q. In which of the following semiconductor are holes minority carriers

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Q. At 0 K, silicon and germanium behave like monoatomic crystals.

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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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