Quick answer: Specific heat capacity is the energy needed to warm 1 kg of a material by 1 °C, and energy transferred equals m × c × Δθ. This Physics 9-10 test on specific heat capacity has 8 questions worth 20 marks, to do in 45 minutes: definition, warming water and constant temperature. The mark scheme is on a separate page; free printable PDF.
Answer all questions. Show your working and give units. Use c(water) = 4200 J/(kg °C). A calculator is allowed. The paper is out of 20 marks.
Level: Physics grades 9-10 (GCSE · IGCSE · O Level · Class 9-10) · Curriculum: GCSE P3, IGCSE 2.2
Question 1 Definition (2 marks)
- State what is meant by specific heat capacity. (1 mark)
- State the unit of specific latent heat. (1 mark)
Question 2 Warming water (3 marks)
Diego in Texas heats 1.8 kg of water from 18 °C to 63 °C. Calculate the energy needed. Use c = 4200 J/(kg °C). (3 marks)Question 3 Constant temperature (2 marks)
Explain why the temperature of boiling water stays at 100 °C although the heater keeps supplying energy. (2 marks)Question 4 Melting wax (3 marks)
A 0.35 kg block of wax at its melting point needs 7.0 × 10⁴ J to melt completely. Calculate the specific latent heat of fusion of the wax. (3 marks)Question 5 Reading the graph (4 marks)
- State the melting point of the substance. (1 mark)
- State the boiling point. (1 mark)
- Calculate how long the substance took to melt. (1 mark)
- The heater power and mass stay the same. Explain why the graph is less steep in the liquid state than in the solid state. (1 mark)
Question 6 Kettle time (3 marks)
A 2.5 kW heater warms 4.0 kg of water from 20 °C to 45 °C. Ignoring losses, calculate the time taken. (3 marks)Question 7 Steam burns (2 marks)
Explain why steam at 100 °C causes a more serious burn than water at 100 °C. (2 marks)Question 8 Coolant (1 mark)
Give one reason why water is used to cool engines. (1 mark)
