KCET 2025 Physics Paper

To determine the terminal voltage across the cell in the given circuit, we start by calculating the current $(i)$ flowing through the circuit. The formula for the current is:$i = \frac{\text{ Voltage }}{\text{ Resistance }} = \frac{2}{4} = \frac{1}{2}\ \mathrm{A}$Next, we calculate the terminal voltage using the formula for terminal voltage, which accounts for the internal resistance of the cell:Terminal voltage $= \text{emf} - i \times r$ where: emf is the electromotive force of the cell ( 2 V in this case), $i$ is the current calculated above $\left( \frac{1}{2}\ \mathrm{A} \right)$, $r$ is the internal resistance of the cell ( $0.1\ \Omega$ ).Substituting these values into the formula:Terminal voltage $= 2 - \left( \frac{1}{2} \times 0.1 \right) = 2 - 0.05 = 1.95\ \mathrm{V}$Therefore, the terminal voltage across the cell is 1.95 V .