Three point charges 1 C , 2 C and 3 C are placed at the comers of an equilateral triangle of side one metre. The work done to move these charges to the corners of another equilateral triangle of side 0.5 ~m is

Step-by-step solution

Initial potential energy of system of charges U _ i = k [ q ₁ q ₂ r + q ₂ q ₃ r + q ₃ q ₁ r ] Substitute the necessary values, aligned & U _ i = k [ 1 2 1 + 2 3 1 + 3 1 1 ] & U _ i =11 k aligned Potential energy of the system of charges whom they move across the corner of equilateral triangle of side 0.5 ~m . U _ f = k [ q ₁ q ₂ r + q ₂ q ₃ r + q ₃ q ₁ r ] Substitute necessary values: aligned & U _ f = k [ 1 2 0.5 + 2 3 0.5 + 3 1 0.5 ] & =22 k aligned Work done is given by: aligned & W=U_f-U_i & =(22-11) k =11 k &