A. resistance of the coil
B. motion of the magnet
C. number of turns of the coil
D. pole strength of the magnet
Related Mcqs:
- A certain amount of current flows through a ring-shaped coil with fixed number of turns. How does the magnetic induction B varies inside the coil if an iron core is threaded into coil without dimensional change of coil ?
A. Decreases
B. Increases
C. Remains same
D. First increases and then decreases depending on the depth of iron inĀ¬sertion - A 200 turn coil having an axial length of 30 mm and a radius of 10 mm is pivoted in a magnetic field having a flux density of 0.8 T. If the coil carries a current of 0.5 A, the torque acting on the coil will be_____________?
A. 8 N-m
B. 0.48 N-m
C. 0.048 N-m
D. 0.0048 N-m - The electromagnet has 50 turns and a current of 1A flows through the coil. If the length of the magnet circuit is 200 mm, what is the magnetic field strength ?
A. 2500 AT/m
B. 250 AT/m
C. 25 AT/m
D. 2.5 AT/m - Magnetism of a magnet can be destroyed by_____________?
A. heating
B. hammering
C. by inductive action of another magnet
D. by all above methods - 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 - 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 - What will be the current passing through the ring shaped air cored coil when number of turns is 800 and ampere turns are 3200 ?
A. 2
B. 4
C. 6
D. 8