A. loud-speakers
B. generators
C. motors
D. all of the above
Related Mcqs:
- The use of permanent magnets is. not made in_____________?
A. magnetoes
B. energy meters
C. transformers
D. loud-speakers - Main causes of noisy solenoid are______________?
A. strong tendency of fan out of laminations at the end caused by repulsion among magnetic lines of force
B. uneven bearing surface, caused by dirt or uneven wear between moving and stationary parts
C. both of above
D. none of the above - The bar magnet has____________?
A. the dipole moment
B. monopole moment
C. A. and B. both
D. none of the above - 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 - The relative permeability of materials is not constant
A. diamagnetic
B. paramagnetic
C. ferromagnetic
D. insulating - 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 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 - Two infinitely long parallel conductors in vacuum any separated 1 metre between centers >then a current of 1 ampere flows the. uk each conductor, produce on each other a force of_________________?
A. 2 x 1(T2 N/m)
B. 2 x KT3 N/m
C. 2 x 10″5 N/m
D. 2x 1(T7 N/m) - The ratio of intensity of magnetisation to the magnetisation force is known as_____________?
A. flux density
B. susceptibility
C. relative permeability
D. none of the above - A permeable substance is one_____________?
A. which is a good conductor
B. which is a bad conductor
C. which is a strong magnet
D. through which the magnetic lines of force can pass very easily
