Q7 of 9 Page 46

2 point charges of +16 μC and –9 μC are placed 8 cm apart in air. The Determine the position of the point where resultant electric field is 0 (zero)

Let, the two charges be Q and q separated by a distance r

q1 =


q2 =


r = 8 cm


E = electric field



Since q1 & q2 have opposite sign so the point at which the electric field is zero will lie beyond the position vector joining the two charges



Let, x be the position of the point P where resultant electric field is zero.


E1 = electric field of q1 at x


E2 = electric field of q2 at x


Given,









Hence at 32 cm from charge the electric field is zero.


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