MCQ
A solid conducting sphere of radius $R_1$ is surrounded by another concentric hollow conducting sphere of radius $R_2.$ The capacitance of this assembly is proportional to
  • A
    $\frac{R_2-R_1}{R_1 R_2}$
  • B
    $\frac{ R _2+ R _1}{ R _1 R _2}$
  • C
    $\frac{ R _1 R _2}{ R _1+ R _2}$
  • $\frac{R_1 R_2}{R_2-R_1}$

Answer

Correct option: D.
$\frac{R_1 R_2}{R_2-R_1}$
$\frac{R_1 R_2}{R_2-R_1}$

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