A large tracked excavator has a mass of 14 000 kg14\,000\text{ kg}14000 kg.
Calculate the weight of the excavator (take global gravitational field strength g=10 N/kgg = 10\text{ N/kg}g=10 N/kg).
The excavator rests on two caterpillar tracks, each of which has a contact area with the muddy ground of 2.8 m22.8\text{ m}^22.8 m2.
Calculate the pressure that the excavator exerts on the ground.
A construction worker walking near the excavator starts to sink into the soft, muddy ground. He places a wide wooden board on the mud and walks along it. Explain, in terms of area and pressure, why he does not sink when walking on the board.
When the excavator's arm lifts a heavy bucket of soil, the load exerts a moment on the arm about its pivot.
Explain what is meant by the moment of a force.
State the two conditions required for any object to be in equilibrium.
188 exam-style questions on CIE IGCSE Physics Pressure, covering Pressure. Each one has a worked solution and a mark scheme showing where the marks go.