The circuit shown in fig 5.230 contains three resistors `R_1 =100Omega, R =50Omega` and `R_3 =20Omega` and cells of emfs `E_12V and E_2` The ammeter indicates a current of 50mA. Determina the currents in the resistors and the emf of the second cell. The internal resistance of the ammeter and of the cells shoudl be

Explanation

Aplyinhg KVL in the loop of ABCD, we get
`E_(1) = (I + 0.05)R_(1) +IR_(2) or I =- 20mA`
Current thorugh `R_(1)` is 30 mA toward right. Current through `R_(2)`
is 20mA toward left. Applying KVL in loop BGEF, we get
`E_(2) = (I + 0.05 )100 + (0.05)20 =8V`