Question

Two metal spheres of equal size and having charges $+8\mu C$ & $-14\mu C$ are mounted on insulated stands. The two spheres are touched together and then separated. Find out the charge on the second sphere ?

• A. Zero
• B. $+11\mu C$
• C. $-6\mu C$
• D. $-3\mu C$
• E. $+2\mu C$

Answer 1

The correct option is D $-3\mu C$

When the spheres touch together, they obtain equal potential. Since the spheres are same in dimension, they obtain equal charges.

Let the charge on each be $q$.

From conservation of charge,

$q+q=+8\mu C+(-14\mu C)$
$⟹q=-3\mu C$