A power supply with electromotive force (e.m.f.) $12\,\text{V}$ and internal resistance $2\,\Omega$ is joined in series to a load resistor. The resistance of the load resistor is changed from $0.5\,\Omega$ to $4\,\Omega$. Which graph shows how the power $P$ dissipated in the load resistor changes with the resistance of the load resistor?
Physics 9702 · AS & A Level · Potential difference and power