Question

What is charging time constant of capacitor?

Answer 1

This transient response time T, is measured in terms of τ = R x C, in seconds, where R is the value of the resistor in ohms and C is the value of the capacitor in Farads




Below we have a circuit of a 9-volt battery charging a 1000µF capacitor through a 3KΩ resistor: One time constant, τ=RC=(3KΩ)(1000µF)=3 seconds. 5x3=15 seconds. So it takes the capacitor about 15 seconds to charge up to near 9 volts.