A. heating
B. hammering
C. by inductive action of another magnet
D. by all above methods
Related Mcqs:
- The commonly used material for shielding or screening magnetism is____________?
A. copper
B. aluminium
C. soft iron
D. brass - The magnetism left in the iron after exciting field has been removed is known as____________?
A. permeance
B. residual magnetism
C. susceptance
D. reluctance - Indicate which of the following material does not retain magnetism permanently
A. Soft iron
B. Stainless steel
C. Hardened steel
D. None of the above - Materials subjected to rapid reversal of magnetism should have______________?
A. large area oiB-H loop
B. high permeability and low hysteresis loss
C. high co-ercivity and high retentivity
D. high co-ercivity and low density - The bar magnet has____________?
A. the dipole moment
B. monopole moment
C. A. and B. both
D. none of the above - In a simple magnetic field the strength of magnet flux_______________?
A. is constant and has same value in energy part of the magnetic field
B. increases continuously from initial value to final value
C. decreases continuously from initial value to final value
D. first increases and then decreases till it becomes zero - A rectangular magnet of magnetic moment M is cut into two piece of same length, the magnetic moment of each piece will be______________?
A. M
B. M/2
C. 2 M
D. M/4 - A square cross-sectional magnet has a pole strength of 1 x 10 Wb and cross sectional area of 20 mm x 20 mm. What is the strength at a distance of 100 mm from the unit pole in air ?
A. 63.38 N/Wb
B. 633.8 N/Wb
C. 6338 N/Wb
D. 63380 N/Wb - When a magnet is in motion relative to a coil the induced e.m.f. does not depend upon____________?
A. resistance of the coil
B. motion of the magnet
C. number of turns of the coil
D. pole strength of the magnet - The working of a meter is based on the use of a permanent magnet. In order to protect the meter functioning from stray magnetic fields______________?
A. meter is surrounded by strong magnetic fields
B. a soft iron shielding is used
C. a plastic shielding is provided
D. a shielding of anon-magnetic material is used
