Question

If $10$ million electrons are removed from a neutral body, then the charge on the body is :

• A. $1.2\times {10}^{-12}C$
• B. $+1.6\times {10}^{-12}C$
• C. $-1.6\times {10}^{-13}C$
• D. ${10}^{-12}C$

Answer 1

The correct option is B $+1.6\times {10}^{-12}C$

charge of each $e^{-}=-1\cdot 6\times {10}^{-19}C$
total charge removed $=-1\cdot 6\times {10}^{-19}\times {10}^6\times 10$
$=-1\cdot 6\times {10}^{-12}C$

Charge on the body $=-$(Total charge removed from the neutral body)

$Q=1\cdot 6\times {10}^{-12}C$