Two cells are connected in opposition as shown. Cell $\mathrm{E}_1$ is of $8 \mathrm{~V}$ emf and $2 \ \Omega$ internal resistance; the cell $E_2$ is of $2 \mathrm{~V}$ emf and $4\ \Omega$ internal resistance. The terminal potential difference of cell $\mathrm{E}_2$ is:
A$10$
B$6$
C$7$
D$45$
JEE MAIN 2024, Diffcult
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B$6$
b $I=\frac{8-2}{2+4}=\frac{6}{6}=1 \mathrm{~A}$
Applying Kirchhoff from $C$ to $B$
$ V_C-2-4 \times 1=V_B $
$ V_C-V_B=6 \mathrm{~V} $
$ =6 \mathrm{~V}$
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