Answer to Question #240170 in Physics for Luyanda

Question

A parallel-plate capacitor has plates of dimensions 4.0cm by 1.5cm separated by a 0.1mm thickness of paper. (a) find its capacitance. (b) what is the maximum charge that can be placed on the capacitor? (c) what are the purposes of the paper separating the two parallel-plates?

Answer 1

(a) The capacitance:

$$C=\frac{\epsilon_0ab }{d}=5.31·10^{-11}\text{ F}.$$

(b) The maximum charge depends on the voltage applied to the plates:

$$Q=CV=(5.31·10^{-11})V\text{ C}.$$

(c) The paper is an insulator that prevents the charges from flowing between the plates.