Question

A current carrying loop is placed in the non- uniform magnetic field whose variation in spaces is shown in fig. Direction of the magnetic field is into the plane of paper. The magnetic force experienced by the loop is:

A. Non-zero
B. Zero
C. Cannot say anything
D. None of the above

Answer 1

Hint - To solve this question firstly we should understand the question , the question is saying that a current carrying loop is placed in a non uniform magnetic field and the variation of magnetic field in space is shown because it is non uniform magnetic field , the direction of magnetic field is given as into the plane and we have to find the force experienced by the loop. So first of all, look at the fig.

Step-By-Step answer:
So, this rectangular loop is symmetric to the central axis, if we look at magnetic field also, the variation of magnetic field and loop is entire setup is in symmetry, it means both the sides are alike, so around this central axis if u find the breadth at both the site it will be zero due to its symmetry, the direction of force here will be in one direction and the direction of force will be exactly opposite.
Each and every pair of loop element located symmetrically with respect to central axis so, it experiences zero net force
Therefore, the loop will experience zero force.

Hence, the correct option is B – zero.

Note - This is an rectangular loop in which the current is flowing in clockwise direction, here the magnetic field, variation in space is given for the first half of cycle it nearly increases and then decreases, so we have to find out what will be the force experienced by this current carrying conductor due to presence of magnetic field and one more thing the magnetic field, the direction of magnetic field is into the plane.