Question

Three charges 2 c,3c,4c are plsced at the corners of

Answer 1

Explanation:

work done on the system is change in their potential energies in the two configurations.

let q1= 1C

q2 = 2C

q3 = 3C

so initial potential energy of the arrangement r=1m

U = k (q1q2/r +q2q3/r + q3q1/r) where k is constant ( 9 * 109)

= k(2+6+3)/1

U initial = 11k ............. (1)

initial potential energy of the arrangement r=0.5 m

Ufinal = k (q1q2/r +q2q3/r + q3q1/r)

=k(2+6+3)/0.5

=22 k ........................ (2)

Work Done = Ufinal - U initial

= 22k - 11k

= 11 k

= 11 * 9*109

= 99 * 109 Joule ( ans )