Question

Force between two identical short bar magnets whose centre are r metre apart is 4.8N when their axes are in same line. If the separation is increased by 2r the force between them is reduced to

Answer 1

Answer:

0.3 N

Explanation:

In magnetic dipole ,  

F α  1/ r⁴  - Force is inversely proportional to radius

Thus, When the separation is made 2r the force is reduced to below :-

the new Force (F) will becomes = 4.8 / 2⁴ = 4.8 / 16 = 0.3 N

Hence the answer is  0.3 N