Question

A parallel plate capacitor consisting of two circular plates of radius 10 cm is being charged by a constant current of 0.15 A . If the rate of change of potential difference between the plates is \(7 \times 10^{8} \mathrm{V} / \mathrm{s}\) then the integer value of the distance between the parallel plates is -

\(\left(\right. \text{Take}, \left.\epsilon_{0}=9 \times 10^{-12} \frac{\mathrm{~F}}{\mathrm{~m}}, \pi=\frac{22}{7}\right) \)_______ \( \mu \mathrm{m}.\)

Answer 1

Answer is: 1320   

Q = cV

\(V=\frac{Q}{c}=\frac{\text { it }}{\left(\frac{\varepsilon_0 A}{d}\right)}\)

\(d=\frac{\varepsilon_0 \pi r^2}{i}\left(\frac{v}{t}\right)\)

Putting values

\(d =\frac{9 \times 10^{-12} \times \frac{22}{7} \times(0.1)^2}{0.15} \times\left(7 \times 10^8\right) \)

\(=1320 \ \mu \mathrm{m} \)