Question

Two point charge Q and 4Q are fixed at a distance of 12cm from each other. Sketch lines of force and locate the neutral point, if any .

Answer 1

For its loction
`(1)/(4 pi epsilon_(0))(Q)/(x^(2))(1)/(4 pi epsilon_(0))(4Q)/((l-x)^(2))`
`((l-x)/(x))^(2)=4` or `x=(l)/(3) =(12)/(3)=4 cm`
Hence neutral point will be at 4 cm from charge Q.