Q. A rare gas having N atoms/m³ is subjected to an electric field E. The electric dipole moment per unit volume is proportional to N and E.

View solution

Q. In an intrinsic semiconductor, at a given temperature T

View solution

Q. The core of a solenoid is made of material of relative permeability μᵣ. A small cavity area dA and length dl is cut in the core. If it is desired that flux density in the cavity should be equal to B0

View solution

Q. A copper specimen has resistivity equal to 1.8 x 10¯⁸ ohm-m at room temperature. At a temperature of 700 K, the resistivity is likely to be

View solution

Q. Assertion (A): Dielectric constant is independent of temperature unless the temperature is extremely high.

Reason (R): For normal temperatures the number of atoms per unit volume is constant.

View solution

Q. As the atoms of rare gases become larger, electronic polarizability

View solution

Q. Ferrimagnetic materials have anti-parallel orientation of equal moments of permanent dipoles.

View solution

Q. Carbon steel has a residual flux density of 1 Wb/m².

View solution

Q. When an atom of polarizability a is placed in an electric field E, the energy stored in atom is 0.5 α E².

View solution

Q. The charge per proton is

View solution

Q. In terms of Planck's constant h, the orbital angular momentum of an electron is

View solution

Q. The merger of hole and free electron is called

View solution

Q. The elements which become superconducting at extremely low temperatures are

View solution

Q. Electrical contact materials used in switches, brushes, relay must possess

View solution

Q. The phenomenon of dielectric hysteresis occurs with

View solution

Q. The induced magnetic dipole moment is independent of the permanent magnetic dipole moment.

View solution

Q. The number of protons in a silicon atom are

View solution

Q. The fact that domains exhibits spontaneous magnetisation is

View solution

Q. Assertion (A): Hall effect is used to determine whether the semi- conductor is p or n type.

Reason (R): Under the influence of field, holes and electrons move in opposite direction.

View solution

Q. The most important set of specifications of transformer oil include

View solution