Question

force between 2 identical short bar magnets whose centres are r metre apart is 4.8 N when their axes are in the same line. if the separation is increased to 2r metre the force b/w them is reduced to ???

Answer 1

If the distance between the two magnets become twice i.e from r to 2r than the force will be the half of it i.e from 4.8 meter to 2.4 meter.

And:- 2.4 metre.

Answer 2

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