Two ice skaters, X and Y, stand at rest facing each other on smooth ice. They push against each other's hands and move apart.
The mass of skater X is 60 kg. The mass of skater Y is 40 kg.
During the push, skater X exerts a force of 120 N on skater Y. Ignore friction.
State the size and direction of the force that skater Y exerts on skater X. Name the law you have used.
Calculate the acceleration of each skater during the push.
The push lasts for 0.50 s.
Calculate the velocity of each skater at the end of the push.
Use your answers to (c) to show that momentum is conserved.
50 exam-style questions on OCR GCSE Physics 2.2 Newton’s laws, covering 2.2.1 Interactions between objects, 2.2.2 Force pairs in interactions, 2.2.3 Forces as vectors, 2.2.4 Newton's first law, 2.2.5 Resolving forces with vector diagrams, 2.2.6 Forces acting on an isolated object, 2.2.7 Free body diagrams and resultant force, 2.2.8 Free body diagrams for balanced forces, 2.2.9 Newton's second law, 2.2.10 Inertia and inertial mass, 2.2.11 Momentum in collisions, 2.2.12 Relating force, mass, velocity and acceleration, 2.2.13 Work done by a force, 2.2.14 Work, stored energy and units of energy, 2.2.15 Power as the rate of energy transfer, 2.2.16 Newton's third law, and 2.2.17 Circular motion and changing velocity. Each one has a worked solution and a mark scheme showing where the marks go.