2. Exercises

A man, of mass 75 kg, stands on a horizontal surface. Assume that the man has two points of contact with the ground.

a) Draw a diagram to show the forces acting on the man.

b) Calculate the magnitude of each of these forces.

An aeroplane circles an airport at a constant speed. Are the forces acting on the aeroplane in equilibrium? Explain your answer.

A helicopter, of mass 800 kg, is rising at a constant rate.

a) Are the forces acting on the helicopter in equilibrium?

b) Calculate the magnitude of the vertical lift force on the helicopter.

Calculate the magnitude of the force that gravity exerts on each of the following objects.

a) A car of mass 1250 kg.

b) A table tennis ball of mass 4 grams.

c) A lorry of mass 4.2 tonnes.