A solar panel receives energy from the Sun at a rate of 7.0 kW.
Thermal energy is transferred from the solar panel to water with an efficiency of 18%.
Cold water of mass 18 kg enters the solar panel every hour.
The specific heat capacity of water is 4200 J/(kg ∘C)4200\text{ J}/(\text{kg}\ {}^\circ\text{C})4200 J/(kg ∘C).
Calculate the temperature increase of the water.
temperature increase = ________________ ∘C{}^\circ\text{C}∘C
State and explain one advantage and one disadvantage of heating the water in a solar panel compared with heating the water in a gas-burning boiler.
advantage: __________________________________________________
explanation: __________________________________________________
disadvantage: __________________________________________________
explanation: __________________________________________________
119 exam-style questions on CIE IGCSE Physics 2.2.2a Internal energy and temperature. Each one has a worked solution and a mark scheme showing where the marks go.