Question

The capacitance of a metallic sphere will be$1\mu F$, if its radius is nearly

• A. 9 $km$
• B. 10$m$
• C. 1.11 $m$
• D. 1.11 $cm$

Answer 1

Answer: (A)

9 $km$

Answer 2

$4\pi\varepsilon_{0}r = 1 \times 10^{- 6}$ ⇒ $r = 10^{- 6} \times 9 \times 10^{9} = 9km$