An electric heater inside a submarine's life-support chamber dissipates 120 W of thermal power when operated from a 12.0 V auxiliary battery.
Due to system modifications, the power supply voltage is reduced to 6.0 V. The heating element is replaced so that the chamber continues to receive 120 W of heating power from the new supply.
What is the percentage decrease in the resistance of the heating element?
25
50
75
83
37 exam-style questions on AQA A Level Physics Current electricity, covering Basics of electricity, Current-voltage characteristics, Resistivity, Circuits, Potential divider, and Electromotive force and internal resistance. Each one has a worked solution and a mark scheme showing where the marks go.