Pearson Edexcel International GCSE
Physics — Topic 5 Paper 3
Solids, liquids and gases · specification 5.1, 5.3–5.7, 5.15–5.22
Time allowed: 30 minutes
Total marks: 25
Candidate name:
Centre / class:
Answer all questions. You may use a calculator. Show your working. Take $g = 10\,\text{N/kg}$.
1
A student finds the density of a sample of cooking oil. She pours $45.0\,\text{cm}^3$ of oil into a measuring cylinder. The mass of this oil is $40.5\,\text{g}$.
(a) Describe how the student should obtain an accurate value for the volume of the oil in the measuring cylinder.
[2]
(b) Describe how she should obtain the mass of the oil (the cylinder is not of negligible mass).
[2]
(c) Calculate the density of the oil in $\text{kg/m}^3$.
[2]
(Total for Question 1 = 6 marks)
2
A person of weight $800\,\text{N}$ walks on snow. First they wear snowshoes of total contact area $0.040\,\text{m}^2$. Later they wear boots of total contact area $0.010\,\text{m}^2$.
(a) Calculate the pressure on the snow when the person wears the snowshoes.
[2]
(b) Calculate the pressure on the snow when the person wears the boots.
[2]
(c) Explain why the person is less likely to sink into the snow when wearing snowshoes.
[2]
(Total for Question 2 = 6 marks)
3
A teacher discusses the kelvin temperature scale with a class.
(a) State the value of absolute zero on the Celsius scale and on the kelvin scale.
[2]
(b) State what happens to the kinetic energy of gas particles at absolute zero.
[1]
(c) Write the equation that converts a Celsius temperature $\theta$ to a kelvin temperature $T$.
[1]
(d) Explain why temperatures must be in kelvin when using $p_1/T_1=p_2/T_2$.
[2]
(Total for Question 3 = 6 marks)
4
Air is trapped in a tyre pump. The pressure of the air is $250\,\text{kPa}$ and its volume is $8.0 \times 10^{-4}\,\text{m}^3$. The piston is pulled out slowly until the volume is $1.0 \times 10^{-3}\,\text{m}^3$. The temperature remains constant.
(a) State two quantities that must remain constant for $p_1V_1=p_2V_2$ to apply.
[2]
(b) Calculate the new pressure of the air.
[3]
(c) State whether the new pressure is larger or smaller than $250\,\text{kPa}$, and give a particle reason.
[2]
(Total for Question 4 = 7 marks)
END OF PAPER 3