A storage battery is connected to a charger for changing with a voltage of 12.5 volts. The internal resistance of the storage battery is `1 Omega`. When the charging current is `0.5 A`, the emf of the storage battery is

Options

A. `13` volts
B. `12.5` volts
C. `12`volts
D. `11.5` volts

Answer

C

Explanation

`V=E+Ir`
`E=V-Ir`
`E=12.5-0.5xx1`
`E=12` volt