Electromotive forces of `E_1` and `E_2` [fig:1.28] are respectively 4V and 8V, `r_1=0.5 Omega,r_2=1 Omega`, Determine the current and the terminal potential difference for each cell.

Explanation

Two two cells are connected in opposition and `E_2 gt E_1`. So,current,
`I=(E_2-E_1)/(r_1+r_2+4.5+(3times6)/(3+6))=(8-4)/(0.5+1+4.5+2)=4/8=0.5A`
Since the two cells are connected in series, current through each cell=0.5 A.
Potential difference across the terminals of the second cell,
`V_2=E_2-Ir_2=8-.5times1=7.5V`
Since current is flowing through the first cell in opposite direction, the potential difference across the terminals of the first cell,
`V_1=E_1+Ir_1=4+05 times 0.5=4.25V`