Two fixed charges `-2 Q ` and `Q` are located at the points with coordinates ( -3 a, 0) and (+3 a, 0) respectively in the ` X- Y` plane .
All the points in the ` X-Y` plane where the electric potential due to the two charges is zero , line on a .

Options

A. straight line
B. ellipse
C. circle
D. parabola

Answer

3

Explanation

`V_(P) = (1)/(4 pi in_(0))[(-2Q)/(sqrt((3a + x^(2)) + y^(2))) + (Q)/(sqrt((3a - x)^(2) + y^(2)))] = 0`
`4[(3a - x)^(2) + y^(2)] = [(3a + x)^(2) + y^(2)]`
`= 3x^(2) + 3y^(2) - 30 ax = 0`
`x^(2) + y^(2) - 10 ax = 0`
This is equation of circle.