A filament lamp and a light emitting diode (LED) lamp each receive the same amount of electrical energy. The LED lamp transfers less energy to the thermal energy stores of the surroundings. Which statement about the LED lamp is correct?
It transfers more energy by light, because less of the same energy supplied is wasted.
It transfers less energy by light, because less energy is transferred to the surroundings.
It has the same efficiency, because both lamps are designed to transfer energy by light.
It transfers the same energy by light, because both lamps receive the same total energy.
128 exam-style questions on Edexcel GCSE Physics 8.3 Power and efficiency, covering 8.3.1 Power and 8.3.2 Efficiency. Each one has a worked solution and a mark scheme showing where the marks go.