Question

Two conducting solid spheres (A & B) are placed at a very large distance with charge densities and radii as shown:

• A. 4 : 1
• B. 1 : 2
• C. 2 : 1
• D. 1 : 4

Answer 1

Answer: (C)

2 : 1

Answer 2

Final potential is same
$⇒\frac{1}{4\pi\epsilon_0}\frac{Q_1}{R}=\frac{1}{4\pi\epsilon_0}\frac{Q_2}{2R}\ \ \ \ \ ....(1)$
Also, $Q_1+Q_2=\sigma.4\pi R^2+\sigma.4\pi(2R)^2\ \ \ \ \ .....(2)$
$⇒\frac{\sigma_1}{\sigma_2}=2.$

So, The correct answer is (C) : 2 : 1