HSC Science Class 12 - Tamil Nadu Board of Secondary Education Question Bank Solutions

State Huygen’s principle.

What is electric power?

What is electric energy?

Derive the expression for power P = VI in electrical circuit.

Write down the various forms of expression for power in electrical circuit.

Four light bulbs P, Q, R, S are connected in a circuit of unknown arrangement. When each bulb is removed one at a time and replaced, the following behavior is observed.

Draw the circuit diagram for these bulbs.

A particle having mass m and charge q accelerated through a potential difference V. Find the force experienced when it is kept under perpendicular magnetic field B is

Two identical coils, each with N turns and radius R are placed coaxially at a distance R as shown in the figure. If I is the current passing through the loops in the same direction, then the magnetic field at a point P which is at exactly at `"R"/2` distance between two coils is-

A bar magnet of length l and magnetic moment p_m is bent in the form of an arc as shown in figure. The new magnetic dipole moment will be-

A flat dielectric disc of radius R carries an excess charge on its surface. The surface charge density is σ. The disc rotates about an axis perpendicular to its plane passing through the centre with angular velocity ω. Find the magnitude of the torque on the disc if it is placed in a uniform magnetic field whose strength is B which is directed perpendicular to the axis of rotation

The potential energy òf magnetic dipole whose dipole moment is `vec"p"_"m" = (- 0.5 hat"i" + 0.4 hat"j")"Am"^2` kept in uniform magnetic field `vec"B" = 0.2hat"i"`T

Why is the path of a charged particle not a circle when its velocity is not perpendicular to the magnetic field?

A circular coil with a cross-sectional area 0.1 cm² is kept in a uniform magnetic field of strength 0.2 T. If the current passing in the coil is 3 A and the plane of the loop is perpendicular to the direction of a magnetic field. Calculate

1. total torque on the coil
2. total force on the coil
3. average force on each electron in the coil due to the magnetic field. (The free electron density for the material of the wire is 10²⁸ m^-3).

A bar magnet is placed in a uniform magnetic field whose strength is 0.8 T. If the bar magnet is oriented at an angle 30° with the external field experiences a torque of 0.2 Nm. Calculate

1. the magnetic moment of the magnet
2. the work is done by the magnetic field in moving it from the most stable configuration to the most its configuration and also compute the work done by the applied magnetic field in this case.

A non – conducting sphere has a mass of 100 g and radius 20 cm. A flat compact coil of wire with turns 5 is wrapped tightly around it with each turns concentric with the sphere. This sphere is placed on an inclined plane such that plane of coil is parallel to the inclined plane. A uniform magnetic field of 0.5 T exists in the region in a vertically upward direction. Compute the current 1 required to rest the sphere in equilibrium.

Compute the torque experienced by a magnetic needle in a uniform magnetic field.

When the current changes from +2A to −2A in 0.05 s, an emf of 8 V is induced in a coil. The co-efficient of self-induction of the coil is

A circular coil with a cross-sectional area of 4 cm² has 10 turns. It is placed at the centre of a long solenoid that has 15 turns/cm and a cross-sectional area of 10 cm². The axis of the coil coincides with the axis of the solenoid. What is their mutual inductance?

What do you mean by self-induction?

What is meant by mutual induction?