Question

ESO014
15.
Two charges 4q and q are placed at a distance l
apart. A third charged particle Q is placed at the
middle of them. If resultant force on q is zero then
the value of Q is :-
(1)q
(3) -q
(4) 2q
(2) – 2q​

Answer 1

Answer:

-q

Explanation:

4q. Q q

l........... L ..........l

for resultant on q is zero Q is a negative charge.

on q, we write eqn. with help of coulombs law as:

kqQ/(l²/4)= 4kq²/l²

by solving this we get Q=q

we know that Q should be negative so,

Q=-q