Question

A capacitor is charged to 8.0×10−4 C , then discharged by connecting a wire between the two plates. 35us after the discharge begins, the capacitor still holds 14 % of its original charge.

What was the average current during the first 35us of the discharge?

Answer 1

The average current is 19.567 A

Solution:

As per the question:

Charge, Q =
`8.0* 10^(- 4)\ C`

Time, t =
`35* 10^(- 6)\ s`

Now,

We know that current is constituted by the rate of transfer of the charge per unit time. Thus we can write:

I =
`(Q)/(t)` (1)

Now, the charge that was transferred is 86 % of the original value.

Therefore,

We replace Q by 0.86Q in eqn (1):

I =
`(0.86* 8.0* 10^(- 4))/(35* 10^(- 6)) = 19.657\ A`