Q. Which of the following is used in temperature alarm circuits?

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Q. n type semiconductors

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Q. The most important primary force of attraction in the formation of solids is

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Q. When two conductors carry currents in the same direction the force is repulsive.

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Q. The number of turns in a coil is doubled. If initial time constant is T, the new time constant is

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Q. When a trivalent impurity is added, the semiconductor becomes

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Q. Iron has a body centred cubic structure.

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Q. The units of polarization of dielectric are

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Q. When a potential is applied across an intrinsic semiconductor, holes flow

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Q. For magnetic shielding, we need a ferromagnetic material.

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Q. Assertion (A): Electronic polarizability increases as atoms becomes larger.

Reason (R): For rare gas, ∈₀(∈ᵣ - 1) E = Nαe, where N is number of atoms/m³ and αe is electronic polarizability of material.

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Q. In a metal, the valence electrons

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Q. All magnetic materials exhibit the phenomenon of saturation.

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Q. On the basis of the type of chemical bonds, solids may be classified into

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Q. The units for intrinsic strength of dielectric are

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Q. Specific resistance of silver is about

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Q. The v-i relation for an arc is v = 44 + 30/i . If v = 50 V, i =

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Q. Assertion (A): If an electron having charge e is revolving in an orbit of radius R and with angular velocity ω, the magnetic dipole moment of orbit is 0.5 eωR².

Reason (R): Orbital angular momentum and magnetic dipole moment are always equal.

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Q. Assertion (A): A capacitor with imperfect dielectric can be represented by a capacitance in parallel with resistance.

Reason (R): For imperfect dielectrics, dielectric constant has real and imaginary parts.

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Q. An atom of a rare gas is placed is an electric field E. Then

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