Question

Two positive charges of 20 $coulomb$ and $Q\mspace{6mu} coulomb$are situated at a distance of $60cm$. The neutral point between them is at a distance of $20cm$ from the $20coulomb$ charge. Charge $Q$ is

• A. $30C$
• B. $40C$
• C. $60C$
• D. $80C$

Answer 1

Answer: (D)

$80C$

Answer 2

At neutral point

$k \times \frac{20}{(20 \times 10^{- 2})^{2}} = k \times \frac{Q}{(40 \times 10^{- 2})^{2}}$ ⇒ Q = 80 C