What will be the magnetic potential difference across the air gap of 2 cm length in magnetic field of 200 AT/m ?

Related Mcqs:

1. 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

2. 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

3. How does the magnetic compass needle behave in a magnetic field ?

   A. It assures a position right angle to magnetic field
   B. It starts rotating
   C. It assures a position which follows a line of magnetic flux
   D. None of the above

4. 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

5. A conductor of length L has current I passing through it, when it is placed parallel to a magnetic field. The force experienced by the conductor will be______________?

   A. zero
   B. BLI
   C. B2LI
   D. BLI2

6. If a copper disc is rotated rapidly below a freely suspended magnetic needle, the magnetic needle shall start rotating with a velocity?

   A. less than that of disc but in opposite direction
   B. equal to that of disc and in the same direction
   C. equal to that of disc and in the opposite direction
   D. less than that of disc and in the same direction

7. Air gap has_________eluctance as compared to iron or steel path?

   A. little
   B. lower
   C. higher
   D. zero

8. 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

9. The uniform magnetic field is______________?

   A. the field of a set of parallel conductors
   B. the field of a single conductor
   C. the field in which all lines of magnetic flux are parallel and equidistant
   D. none of the above

10. A 300 mm long conductor is carrying a current of 10 A and is situated at right angles to a magnetic field having a flux density of 0.8 T ; the force on the conductor will be____________?

    A. 240 N
    B. 24 N
    C. 2.4 N
    D. 0.24 N