A copper wire is held between the poles of a magnet
The current in the wire can be reversed. The pole of the magnet can also be changed
over. In how many of the four directions shown can the force act on the wire?
- 1
- 2
- 3
- 4
Answer:
By using the Flemming’s left hand rule, two conclusions can be drawn:
-
When the
direction of current is kept constant
(fixed in either direction), the
magnetic field can be varied in 2 directions
(W-E, E-W).
The resultant force on the wire can be in 2 directions: upwards or downwards (N or S) (respectively) -
When the direction of
magnetic field is kept constant
(fixed in either direction), the
current can be varied in 2 directions
(inwards and outwards).
The resultant force on the wire can be in 2 directions: upwards or downwards (N or S) (respectively)
Therefore, the correct answer is (b) 2 (Either North or South)
