Questions on Magnetism (Class 12 Physics)

QUESTIONS

1. A charged particle moving in a perpendicular uniform magnetic field penetrates a layer of lead and thereby loses half of its kinetic energy. How will the radius of curvature of its path changes.
2. The energy of a charged particle moving in a uniform magnetic field does not change, why ?
3. State property of material of the wire used for the suspension of the coil in a moving cell galvanometer.
4. Can you accelerate a neutron by cyclotron ?
5. What is the radial magnetic field ?
6. Does the magnetic field exert a force on a static charge ?
7. What is the shape of magnetic field lines when current is straight or circular ?
8. Why does a solenoid tend to contract when a current passes through it ?
9. Which one has lowest resistance: ammeter, voltmeter and galvanometer ?
10. Name some magnetic and non-magnetic substances.

ANSWERS

1. r ∝ √E , radius is reduced to 1/ √ 2 times
2. Force is perpendicular to the direction of motion.
3. It should have low torsional constant, high tensile strength, low temperature coefficient of resistance. It should be a non magnetic substance and a good conductor of electricity.
4. No
5. Where the plane of the coil always lies in the direction of magnetic field.
6. No
7. Circular, when current is straight;
   Straight, when current is circular.
8. Due to mutual attraction between the coil turns.
9. Ammeter
10. Magnetic substance: iron, cobalt, nickel, steel, etc.
    Non-magnetic substances: brass, paper, wood, etc.