Question

The outer cylinder of a cylindrical capacitor of length 0.15 m and radial 1.61 cm and 1.5 cm is earthed while inner cylinder of this capacitor is given a charge of `8 muC`. Find the capacitance and potential of inner part of the capacitor.

Answer 1

Here, l = 0.15 m,
`r_(b) = 1.61xx10^(-2)m, r_(a) = 1.50xx10^(-2) m`
`q = 8.0xx10^(-6) C, C = ?, V = ?`
For cylindrical capacitor,
`C = (2pi in_(0) l)/(2.3031 log_(10) ((r_(b))/(r_(a))))`
`= (2pi(8.854xx10^(-12)) (0.15))/(2.303 log_(10) ((1.61xx10^(-2))/(1.50xx10^(-2))))`
`C = 1.18xx10^(-10) F`.
`V = (q)/(C ) = (8.0xx10^(-6))/(1.18xx10^(-10)) = 6.78xx10^(4) V`