Question

three point charges of 1C, 2Cand 3C are placed at the corners of an equilateral triangle of side 1m find the work done to move these charges to corners of a similar equilateral triangle of side 0.5m​

Answer 1

Answer:

99 * 109  Joule

Explanation:

Dear Student,

 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