Which statement describes a closed system?
a system in which the objects all move at a constant speed
a system in which the objects all have the same total mass
a system in which no energy is transferred by heating
a system in which no external force acts on the objects
40 exam-style questions on AQA GCSE Physics 5.7 Momentum (HT only), covering 5.7.1 Momentum is a property of moving objects, 5.7.2 Conservation of momentum, and 5.7.3 Changes in momentum. Each one has a worked solution and a mark scheme showing where the marks go.