IB Physics HL B.1.7 Thermal Transfer Direction Question Bank
Practise HL thermal-transfer questions on thermal capacity, gradients and equilibrium timing using real experimental evidence.
- Syllabus
- First assessment 2025
- Course
- Physics HL
- Level
- HL
Practise HL thermal-transfer questions on thermal capacity, gradients and equilibrium timing using real experimental evidence.
The equipment shown in the diagram was used by a student to investigate the variation with volume, of the pressure p of air, at constant temperature. The air was trapped in a tube of constant cross-sectional area above a column of oil.

The pump forces oil to move up the tube decreasing the volume of the trapped air.
The student measured the height H of the air column and the corresponding air pressure p. After each reduction in the volume the student waited for some time before measuring the pressure. Outline why this was necessary.
in order to keep the temperature constant in order to allow the system to reach thermal equilibrium with the surroundings/OWTTE
Marking guidance:
Accept answers in terms of pressure or volume changes only if clearly related to reaching thermal equilibrium with the surroundings.
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