Q. Assertion (A): In imperfect capacitors, the current does not lead the applied ac voltage by 90°.
Reason (R): When subjected to ac fields, the dielectric constant can be expressed as ∈'r - j∈"r.

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Q. In atomic physics, a state with l = 0 is called p state.

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Q. If a sample of germanium and a sample of silicon have the same impurity density and are kept at room temperature

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Q. When an electric field E is applied to solid and liquid insulating materials, the internal field Ei acting at the location of atom is such that

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Q. Which element exhibits the property of inertia?

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Q. For a permanent magnetic material

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Q. In a coaxial cable, braided copper is used for

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Q. The hysteresis phenomenon in ferromagnetic materials exists at all temperatures.

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Q. Assertion (A): Magnetic susceptibility of diamagnetic materials is much less than that of paramagnetic materials.
Reason (R): For diamagnetic as well as paramagnetic materials, μᵣ is nearly equal to 1.

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Q. The conductivity of intrinsic semiconductor is given by

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Q. The core of a coil has a length of 10 cm. The self inductance is 8 mH. If the core length is doubled, all other quantities remaining the same, the self inductance will be

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Q. The minority carrier life time and diffusion constant in a semiconducting material are 100 μs and 100 cm²/s respectively. The diffusion length of carriers is

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Q. Assertion (A): Electronic and Ionic polarization in a polyatomic gas are independent of temperature.
Reason (R): The orientation polarization is independent of temperature.

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Q. Two materials having temperature coefficients of 0.004 and 0.0004 respectively are joined in series. The overall temperature coefficient is likely to be

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Q. Diamond is a paramagnetic material.

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Q. Which capacitor-store higher amount of energy?

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Q. Above ferroelectric curie temperature, spontaneous polarization in ferroelectric materials becomes stronger.

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Q. In paramagnetic materials

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Q. Assertion (A): Atomic number of sodium is 11.
Reason (R): Sodium has a body centred cubic lattice.

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Q. The number of valence electrons in pentavalent impurity is

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