Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

Let Q and W denote the amount of heat given to an ideal gas and the work done by it in an isothermal process.

1. Q = 0
2. W = 0
3. Q ≠ W
4. Q = W

A metal sheet is placed in front of a strong magnetic pole. A force needed to:

The phenomenon of rotation of plane polarized light is called:

The current in a coil of inductance 5 H decreases at the rate of 2 A/s. The induced e.m.f. is

(a) 2 V

(b) 5 V

(c) 10 V

(d) – 10 V

Which of the following isotopes is likely to be most stable?

When charged particle enters-a uniform magnetic field, its K.E:

A rectangular coil 20 cm × 20 cm  has 100 turns and carries a current of 1 A. It is placed in a uniform magnetic field       B  = 0.5 T with the direction of magnetic field parallel to the plane of the coil. The magnitude of the torque required to hold this coil in this position is

(a) Zero

(b) 200 N-m

(c) 2 N-m

(d) 10 N-m

The capacitance of a capacitor does not depend on:

1. The shape of the plates.
2. The size of the plates.
3. The charges on the plates.
4. The separation between the plates.

Which one of the following statements is true

(a) An object situated at the principle focus of a concave lens will have its image formed at infinity

(b) Concave mirror can give diminished virtual image

(c) Given a point source of light, a convex mirror can produce a parallel beam of light

(d) The virtual image formed in a plane mirror can be photographed

Absorption of X-ray is maximum in which of the following different sheets

(a) Copper

(b) Gold

(c) Beryllium

(d) Lead