Solveeit Logo
Login

Question

Physics Question on electrostatic potential and capacitance

A metallic sphere of radius 18 cm18 \,cm has been given a charge of 5×10−6 C5 \times 10^{-6} \, C The energy of the charged conductor is

A

0.2 J0.2 \, J

B

0.6 J0.6 \, J

C

1.2 J1.2 \, J

D

2.4 J2.4 \, J

Answer

0.6 J0.6 \, J

Explanation

Solution

Here r=18 cm=18×10−2 mr = 18 \,cm=18\times10^{-2}\, m, q=5×10−6 Cq=5\times10^{-6}\, C As C=4πε0r=18×10−29×109=2×10−11 FC=4\pi\varepsilon_{0} r=\frac{18\times10^{-2}}{9\times10^{9}}=2\times10^{-11}\, F Energy of charged conductor is U=q22C=(5×10−6)2C2×2×10−11 FU=\frac{q^{2}}{2C}=\frac{\left(5\times10^{-6}\right)^{2}C}{2\times2\times10^{-11}\,F} =0.625 J=0.625\, J