Q147 / 160 · TS EAMCET 2021 (04 Aug Shift 2) · Physics

Consider a spherical drop of mercury of radius R with capacitance C=4πεR. If two such droplets combine to form a larger one, what would be its capacitance in terms of C ?

  • A
    31/3C
  • B
    32/3C
  • C
    22/3C
  • Correct answer
    D
    21/3C

Solution

The volume of the bigger drop should be the same as the sum of the volume of two smaller drops if the radius of the bigger drop is R' and volume of smaller drops is R each, then, 43πR'3=2×43πR3⇒R'=213R, so the capacitance after combination becomes, C'=C×213.

Hence, the correct answer is option: 'D'.

More Capacitance Questions