Available practice: 94 of 100 marks. Parts 3(a)(i), 7(a), 8(a) await marking support. Scores cover available parts only.
(a)(i)State the magnitude and unit of absolute zero on the thermodynamic temperature scale.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[1 mark]
(a)(ii)Explain why temperature measured using a laboratory liquid-in-glass thermometer does not give a measurement of thermodynamic temperature.
Answer guidance
Explain Give reasons, not just what happens. Each distinct reason is usually worth a mark.
[1 mark]
Fig. 2.1 shows a simplified diagram of a type of thermometer called a platinum resistance thermometer. The glass tube is immersed in the environment for which the temperature is to be determined. The resistance between the terminals X and Y is measured. Fig. 2.2 shows the variation of the resistivity ρ of platinum with thermodynamic temperature T.
(b)(i)Explain how Fig. 2.2 shows that platinum is a suitable metal for use in a resistance thermometer.
Answer guidance
Explain Give reasons, not just what happens. Each distinct reason is usually worth a mark.
[2 marks]
A platinum resistance thermometer consists of a platinum wire wound on a plastic strip inside a large glass tube, which is immersed in the environment whose temperature is to be determined .
(b)(ii)Suggest a reason why a platinum resistance thermometer is not suitable for measuring a rapidly changing temperature.
Answer guidance
Suggest More than one answer may be acceptable, so long as it is consistent with the physics.
[1 mark]
(b)(iii)Suggest a type of thermometer that is suitable for measuring a rapidly changing temperature.
Answer guidance
Suggest More than one answer may be acceptable, so long as it is consistent with the physics.
[1 mark]
A negative temperature coefficient thermistor may be used as a type of resistance thermometer.
(c)State one way in which the variation with temperature of the resistance of a thermistor differs from that of a platinum wire.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[1 mark]
9702/41/M/J/24Cambridge International AS & A Level Physics 9702 · May/June 2024 · Paper 4 variant 1 · Question 2
