Capacitor Charging: An uncharged capacitor is the load on a switching circuit. The initial capacitor voltage is 0 V and the final capacitor voltage is 100 V. If the charging time constant is 1 millisecond, what is the capacitor voltage 1 millisecond after the charging begins?

Answer: No matter the contents of the switching circuit, given an initial voltage of 0 V, a final voltage of 100 V, and a charging time constant of 1 ms, the capacitor voltage equals 63.2 V after 1 millisecond.

NOTE: Using the equation shown below, the Visual Calculator will work out the capacitor voltage for any value of t. For instance, when t = 0.1 ms, v = 9.52 V. When t = 2.5 ms, v = 91.8 V. When t = 5 ms, v = 99.3 V, and so on.

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