Two charges of ` 10 mu C and 20 muC ` respectively are placed at points A and B respectively separated by a distance of 60 cm . The distance of the point P from A, where the net electric field is zero, is
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Options

A. 20 cm
B. 30 cm
C. 40 cm
D. 15 cm

Answer

A

Explanation

If A =r cm , then ` (q_A)/(r^(2)) =(q_B)/((60-r)^(2)) rArr (10muC )/(r^(2)) =(40 mu C )/((60-r)^(2)) rArr r= 20 cm `