Question

Find the time constant of a capacitor with capacitance of 2 microfarad having an internal resistance of 4 megaohm.

(a) 2

(b) 0.5

(c) 8

(d) 0.25

The question was asked in final exam.

Origin of the question is Maxwell Law in Time Varying Fields topic in section Maxwell Equations of Electromagnetic Theory

Answer 1

Right option is (c) 8

Explanation: The time constant of capacitor is given by T = RC, where R = 4×10^6 and C = 2×10^-6. Thus T = 4×10^6 x2x10^-6 = 8 seconds.