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The charge on a capacitor decrease eta t...

The charge on a capacitor decrease `eta` time in time `t`, when it discharging through a circuit with a time constant` tau`

A

`t= eta tau`

B

`t = tau 1n eta`

C

`t = tau(1n eta-1)`

D

`t = tau 1n(1-1/(eta))`

Text Solution

Verified by Experts

The correct Answer is:
B
`q=q_(0)e^(-t//tau)`
`(q_(0))/(eta)=q_(0)e^(-t//tau)`
`e^(t//tau)=eta implies t=tau ln eta`
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