Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

Which of the following, the most suitable material for making permanent magnet is

(a) Steel

(b) Soft iron

(c) Copper

(d) Nickel

A current of 10 ampere is flowing in a wire of length 1.5 m. A force of 15 N acts on it when it is placed in a uniform magnetic field of 2 tesla. The angle between the magnetic field and the direction of the current is

(a) 30 °

(b) 45 °

(c) 60 °

(d) 90 °

The nucleus   after two successive   decays will give

(a)

(b)

(c)

(d)

In a parallel plate capacitor, the capacity increases if:

The particles emitted by radioactive decay are deflected by magnetic field. The particles will be

(a) Protons and α - particles	(b) Electrons, protons and α -particles
(c) Electrons, protons and neutrons	(d) Electrons and α -particles

In the circuit diagram shown in the adjoining figure, the resultant capacitance between P and Q is

(a) 47 μF

(b) 3 μF

(c) 60 μF

(d) 10 μ F

The electric field lines are crowded where electric field is:

Find the false statement.

To convert mechanical energy into electrical energy, one can use:

1. DC dynamo.
2. AC dynamo.
3. Motor.
4. Transformer.

The distance moved by a particle in simple harmonic motion in one time period is:

1. A
2. 2A
3. 4A
4. zero.