A magnetic field exists around____________?

Related Mcqs:

1. 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

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

   A. 2 AT
   B. 4 AT
   C. 6 AT
   D. 10 AT

3. 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

4. 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

5. 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

6. The change of cross-sectional area of conductor in magnetic field will affect______________?

   A. reluctance of conductor
   B. resistance of conductor
   C. A. and B. both in the same way
   D. none of the above

7. 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

8. 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

9. 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

10. A material which is slightly repelled by a magnetic field is known as_____________?

    A. ferromagnetic material
    B. diamagnetic material
    C. paramagnetic material
    D. conducting material