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: __________________________________________________
528 exam-style questions on CIE IGCSE Physics 2.2 Thermal properties and temperature, covering 2.2.1 Thermal expansion of solids, liquids and gases, 2.2.2a Internal energy and temperature, 2.2.2b Specific heat capacity, 2.2.3a Melting, boiling, condensation and solidification, 2.2.3b Evaporation, and 2.2.3c Cooling by evaporation. Each one has a worked solution and a mark scheme showing where the marks go.