Question

Two point charges $+8\mu C$ and $+12\mu C$ repel each other with a force of $48N$. When an additional charge of $-10\mu C$ is given to each of these charges (the distance between the charges is unaltered), then the new force is:

• A. repulsive force of $24N$
• B. attractive force of $24N$
• C. repulsive force of $2N$
• D. attractive force of $2N$

Answer 1

The correct option is D attractive force of $2N$

$q_1=+8\mu C$

$q_2=+12\mu C$

$F_1=48N$

Now, $q_1^{\prime }=-2\mu C$

and, $q_2^{\prime }=+2\mu C$

So, $\frac{F_1}{F_2}=\frac{q_1{q}_2}{q_1^{\prime }{q}_2^{\prime }}$

$F_2=2N$