Q. The respective radii of the two spheres of a spherical condenser are $12\ cm$ and $9\ cm.$ The dielectric constant of the medium between them is 6. The capacity of the condenser will be
A) 240 $pF$
B) 240 $\mu F$
C) 240 $F$
D) None of the above
Explanation
(a) $C = 4\pi\varepsilon_{0}K\left\lbrack \frac{ab}{b - a} \right\rbrack = \frac{1}{9 \times 10^{9}}.6\left\lbrack \frac{12 \times 9 \times 10^{- 4}}{3 \times 10^{- 2}} \right\rbrack$
$= 24 \times 10^{- 11} = 240\ pF$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.