Question

Two point charges +4e and +e are kept 8m apartvin air a third point charge q is kept between the two charges so that it is in equilibirium. Find its position​

Answer 1

HEY MATE!

since both the charges are positive and npt equal therefore the charge should be kept in between the two given charges +4 and +1.

To stay in equilibrium condition force of +4 and +1 on q must be equal.

Let us assume the distance of 'q' from +1 charge is x m, therefore distance from +4 charge is (8-x).

Therfore applying Coloumb's Law :

k(4)(q)/(8-x)^2 = k(1)(q)/x^2

4x^2 = (8-x)^2

=> 3x^2 +16x -64 = 0

=> 3x^2 +24x - 8x - 64 =0

=> (3x-8)(x+8) = 0

Hence, x = 8/3 ANSWER

Hope it helps

HAKUNA MATATA :))