Question

Two charges each +q units are placed along a line. a third charge q is placed between them. at what position and for what value of q will the system be in equilibrium

Answer 1

The two point charges +9e  and +e  are placed at a distance of 16cm from  each other .At what point between the charges .At what point between the charges should the third charge q be placed so that it remains in equilbirium?

Three point charges q1 ,q2,q3 are in line at equal distances q2 and q3 are in sign .Find the magnitude and sign of q1 ,if the net force on q3 is zero.

ABC is an equilateral triangle of side 10 m and D is the midpoint of BC. charges of +100 miocrocoulomb ,-100 microcoulomb and +75microcoulomb are placed at B C and D respectively .Find the force on a +microcoulomb placed at A.

At each of the four corners of a square  of side a ,a charge +q is placed  freely .What charge should be placed at the centre so that the whole system be in equilbirium?

Answer 2

Asuuming -q is place x distance from one and a-x from the other.
Force = Kq1q2/r2
where q1=first charge
q2=second charge
r=distance between the charges.
K=constant
Force equilibrium balancing will give:
-KqQ/(x)2=-KqQ(a-x)2
x=a-x
x=a/2 that is exactly in between the line joing the charges.