Thermodynamics
Definitions: Thermodynamics
Exam question
State what is meant by the internal energy of a system.
9702/41 · May/Jun 2025 · Q4(a)(i)
Model answer
The sum of the random kinetic energies and intermolecular potential energies of the particles in the system.
Exam question
State the first law of thermodynamics.
9702/42 · Oct/Nov 2025 · Q4(a)
Model answer
The increase in internal energy of a system equals the thermal energy transferred to the system by heating plus the work done on the system.
