Q165 / 180 · KCET 2023 · Physics
Ten identical cells each emf $2 \mathrm{~V}$ and internal resistance $1 \Omega$ are connected in series with two cells wrongly connected. A resistor of $10 \Omega$ is connected to the combination. What is the current through the resistor?
- A$1.8 \mathrm{~A}$
- B$2.4 \mathrm{~A}$
- Correct answerC$0.6 \mathrm{~A}$.
- D$1.2 \mathrm{~A}$
Solution
According to given situation,
Net emf of the combination,
$E_{\text {net }}=8 \times$ emf of one cell $-2 \times$ emf of one cell
$=8 \times 2-2 \times 2=12 \mathrm{~V}$
Equivalent resistance of the circuit
$R^{\prime}=10 r+R=10 \times 1+10=20 \mathrm{~V}$
$\therefore$ Current through the resistor,
$I=\frac{E_{\mathrm{net}}}{R^{\prime}}=\frac{12}{20}=0.6 \mathrm{~A}$
Hence, the correct answer is option: 'C'.