Magnetism and Matter MCQ Quiz - Multiple Choice Questions & Answers Page 2

11. The strength of the earthcs magnetic field is

1. constant everywhere.
2. zero everywhere.
3. having very high value.
4. vary from place to place on the earth's surface.

12. The relation between geometric length (L) and magnetic length (L_m) is:

1. L_m = 56 L_g
2. L_m = 65 L_g
3. L_m = L_g
4. L_m = 2RY;UL L_g

13. The radius of curvature of the path of charged particle in a uniform magnetic file is directly proportional to the

1. charge on fie particle
2. Momentum of particle
3. energy of particle
4. Strength of field

14. The primary origin of magnetism lies in

1. atomic current and intrinsic spin of electrons.
2. polar and non polar nature of molecules.
3. pauli exclusion principle.
4. electronegative nature of materials.

15. The neutral point in the magnetic field of a horizontally placed bar magnet is a point where the magnetic field due to that bar magnet is:

1. zero
2. more than that of earth
3. less than that of earth
4. equal to that of earth

16. The net magnetic flux through any closed surface, kept in a magnetic field is

1. zero
2. μ04π
3. 4πμ0
4. 4μ0π

17. The material suitable for making electromagnets should have

1. high retentivity and high coercivity.
2. low retentivity and low coercivity.
3. high retentivity and low coercivity.
4. low retentivity and high coercivity.

18. The Mariner's compass is provided with Gimbals arrangement so as to :

1. keep the needle always horizontal
2. give a direct reading of declination
3. give the direct value of dip
4. all of the above

19. The magnetic lines of force inside a bar magnet:

1. do not exist
2. depends on area of cross-section of bar magnet
3. are from N-pole to S-pole of the magnet
4. are from S-pole to N-pole of the magnet.

20. The magnetic field strength due to a short bar magnet directed along its axial line at a distance r is B. What is its value at the same distance along the equatorial line?

1. B
2. 2B
3. B2
4. B4