If at t = 0 the switch `S_(w)` is closed , then the charge on capacitor (initially unchanged)in the given circuit when the current through battery becomes 50 % of its maximum value is (assume battery is ideal)

Options

A. `(C epsilon)/(3)`
B. `(C epsilon)/(2)`
C. `(C epsilon)/(4)`
D. `C epsilon`

Answer

D

Explanation

`I_("max") = (2epsilon)/(R ) " at " t = 0`
`I= (epsilon)/(R ) " at " t = prop`
so charge on the capacitor is `C_(epsilon)`, when current is `50%` of maximum current.