Question

explain the answer plz

Answer 1

aapka question clear samjh nhi aa raha h??

Answer 2

We know that formula of force acting on the charged particles is F=Kq1q2/r^2
Here in this question the charges are kept constant and K is already a constant so it can be thus said that now the force is only dependent on the distance between them i.e. r
now F1/F2 = r2^2/r1^2
r1 = 5 and r2= 20
therefore F1/F2 = (20)^2/(5)^2
F1/F2 = 400/25
F1/F2 = 16
therefore F2 = F1/ 16