Two electric charges of 9 `mu`C and -3 `mu`C are placed 0.16 m apart in air. There will be a point P at which electric potential is zero on the line joining two charges and in between them. The distance of P from 9 `mu`C is

Options

A. 0.14 m
B. 0.12 m
C. 0.08 m
D. 0.06 m

Answer

(b)

Explanation

Electric Potential at point `P, V = V_(1) + V_(2) or V_(1) + V_(2) = 0`
`V_(1) = -V_(2)`
`rArr 1/4 pi epsilon_(0) q_(1)/r_(1) = -1/4 pi epsilon_(0) q_(2)/r_(2)`
`9/x = -(-3)/(0.16 - x)`
`3(0.16 - x) = x`
`rArr 0.48 - 3x = x `
4x = 0.48
`:. x = 0.12 m`