A pneumatic hammer uses a piston of mass 0.75 kg0.75\text{ kg}0.75 kg to strike a heavy steel chisel into a rock face. Just before the piston impacts the chisel, it is travelling downwards with a velocity of 12 m/s12\text{ m/s}12 m/s.
State the relationship between momentum, mass, and velocity.
Calculate the momentum of the piston just before it hits the chisel. State the unit.
The piston is brought to rest in 0.015 s0.015\text{ s}0.015 s during the collision. Calculate the average force exerted on the piston to cause this change in momentum.
As the chisel enters the rock, the chisel exerts a force on the rock. At the same time, the rock exerts a force on the chisel. Explain how these two forces are related.
The chisel has a wide, flat strike-cap at its top end (where the piston strikes it) and a narrow, wedge-shaped tip at the bottom end (which cuts into the rock). Explain why the chisel exerts a much greater pressure on the rock than the piston does on the chisel strike-cap.
56 exam-style questions on Edexcel IGCSE Physics Forces, movement, shape and momentum. Each one has a worked solution and a mark scheme showing where the marks go.