Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

The equivalent resistance between x and y in the circuit shown is

(a) 10 W

(b) 40 W

(c) 20 W

(d)

Choose the correct statement:

The lead marked with the arrow is the _______.

The capacity of a condenser in which a dielectric of dielectric constant 5 has been used, is  C. If the dielectric is replaced by another with dielectric constant 20, the capacity will become

(a)

(b) 4C

(c)

(d) 2C

Light energy emitted by stars is due to

(a) Breaking of nuclei	(b) Joining of nuclei
(c) Burning of nuclei	(d) Reflection of solar light

Of the following properties, the photon does not process:

Which of the following is an example of a direct band gap intrinsic semiconductor?

A uniform conducting wire ABC has a mass of 10g. A current of 2A flows through it. The wire is kept in a uniform magnetic field B = 2T. The acceleration of the wire will be

(a) Zero	(b) 12  along  y-axis
(c) 1.2  along y-axis	(d) 0.6  along y - axis

 When is the conduction current the same as the displacement current?

The resistance of 10 metre long potentiometer wire is 1ohm/meter. A cell of e.m.f. 2.2 volts and a high resistance box are connected in series to this wire. The value of resistance taken from resistance box for getting potential gradient of 2.2 millivolt/metre will be

(a) 790 Ω

(b) 810 Ω

(c) 990 Ω

(d) 1000 Ω