Question

Two point charges Q and -2Q are placed some distance apart. If the electric field at the location of Q is , the field at the location of – 2Q is

• A. $\overrightarrow{E}$
• B. $-\overrightarrow{E}$
• C. $+\frac{\overrightarrow{E}}{2}$
• D. $-\frac{\overrightarrow{E}}{2}$

Answer 1

The correct option is C $+\frac{\overrightarrow{E}}{2}$

$\overrightarrow{E}=-\frac{1}{4\pi {ϵ}_0}\frac{2Q}{r^2}\to \left(1\right)$
Electric Field at - 2Q :- $\underset{E_1}{\to }=\frac{1}{21\pi {ϵ}_0}\frac{Q}{r^2}$
$\underset{E_1}{=}+\frac{\overrightarrow{E}}{2}$