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_____________?

Related Mcqs:

1. 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 in¬sertion

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. 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

4. 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

5. Which of the following is the unit of magnetic flux density ?

   A. weber
   B. lumens
   C. tesla
   D. none of the above

6. 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

7. 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

8. 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

9. The stray line of magnetic flux is defined as_____________?

   A. a line vertical to the flux lines
   B. the mean length of a ring shaped coil
   C. a line of magnetic flux in a non-uniform field
   D. a line of magnetic flux which does not follow the designed path

10. The materials are a bit inferior conductors of magnetic flux than air

    A. ferromagnetic
    B. paramagnetic
    C. diamagnetic
    D. dielectric