Two spherical conductors $A$ and $B$ of radii $a$ and $b$ $(b > a)$ are placed in air concentrically. $B$ is given a charge $+Q$ and $A$ is grounded. The equivalent capacitance of this system is:

  • A
    $4\pi \varepsilon_0 \frac{ab}{b - a}$
  • B
    $4\pi \varepsilon_0 (a + b)$
  • C
    $4\pi \varepsilon_0 b$
  • D
    $4\pi \varepsilon_0 \frac{b^2}{b - a}$

Explore More

Similar Questions

Sixty-four drops are joined together to form a bigger drop. If each small drop has a capacitance $C$,a potential $V$,and a charge $q$,then the capacitance of the bigger drop will be

$A$ cylindrical capacitor has two co-axial cylinders of length $20 \, cm$ and radii $2r$ and $r$. The inner cylinder is given a charge of $10 \, \mu C$ and the outer cylinder a charge of $-10 \, \mu C$. The potential difference between the two cylinders will be:

The capacity of a conductor does not depend upon:

The graph shows the variation of voltage $V$ across the plates of two capacitors $A$ and $B$ versus the charge $Q$ stored in them. Then:

$A$ capacitor of capacitance $C$ is charged to a potential $V$. The flux of the electric field through a closed surface enclosing the positive plate of the capacitor is $......$

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo