Question

Consider a square of side p = 2.40 cm with charges of q = +7.80 μC at each corner. Find the potential at the center of the square.

Answer 1

A= B= C = D =  +7.80 μC

TO CALCULATE THE POTENTIAL AT THE CENTER

Potential by a charge ' q ' at a distance 'r' from it is

As potential is a scalar quantity we can individually find the potential at center by each charge and sum them up to get the net potential at the center .

distance of each charge from the center is 'diagonal/2' = 2.4/2

= (2.4 / ) cm

= 1.7 cm

= 0.017 m

potential at center by each charge is

  

Therefore , the net potential at the center = 4V

= {4 x ( 7.8 x 10 -6 C) x 9 × 109 Nm2/C2 } / 0.017 m

= 1.6517 x 107 N.m/C

= 1.6517 x 107 J/C

= 1.6517 x 107 V

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