Question

Two charges of 40 microcoulomb and management microcoulomb are placed at a certain distance apart the destiny kept at the same distance the ratio of initial to final force between them is

Answer 1

Electric field is zero between two changes means at point electric field of both charge same . let 60-r be distance from 36 micro c charge so

k*4/r^2=k*36/(60-r)^2

1/r^2=9/(60-r)^2

take sq root both side

1/r=3/(60-r)

60-r=3r

60=4r

r=60/4=15

zero field from lager charge is 60-15=45cm

I THINK THIS MAY USEFUL TO YOU