A capacitor of 4mF is connected to a 15 V supply through 1 mega ohm resistance. The time taken by the capacitor to charge upto 63.2 % of its final charge will be
Answer & explanation
Correct answer: option 3
$ q = 0.632 q_0 = q_0 e^{-\frac{t}{RC}} $
$ 0.632 = e^{-\frac{t}{RC}} $
$ t = RC = 4s$