Electrostatics — Physics STD 12 Science — Question

A voltmeter of resistance 1000 Ω  gives full scale deflection when a current of 100 mA flow through it. The shunt resistance required across it to enable it to be used as an ammeter reading 1 A at full scale deflection is

(a) 10000 Ω

(b) 9000 Ω

(c) 222 Ω

(d) 111 Ω

In a p-n junction:

In Young’s double slit experiment, the central bright fringe can be identified

(a) By using white light instead of monochromatic light

(b) As it is narrower than other bright fringes

(c) As it is wider than other bright fringes

(d) As it has a greater intensity than the other bright fringes

 Dielectrics are _____________?

Potential at a point x-distance from the centre inside the conducting sphere of radius R and charged with charge Q is

(a)

(b)

(c)

(d) xQ

The force of attraction or repulsion between two charges is given by __________.

Which of the following will change the time period as they are taken to moon?

1. A simple pendulum.
2. A physical pendulum.
3. A torsional pendulum.
4. A spring-mass system.

In case of the electromagnetic waves the angle between the electric and magnetic field vectors is.

A condenser has a capacity 2μF and is charged to a voltage of 50 V. The energy stored is

(a) 25 × 105 Joule

(b) 25 Joule

(c) 25 × 10 erg

(d) 25 × 103 erg