1) The diagram represents a cyclist making a left turn on a rough road surface at constant speed v, as viewed from behind. The total mass of the bicycle and rider is m and their combined centre of gravity is at G.

If R is the resultant force of the normal contact force and the frictional force, which vector diagram represents the directions of the forces acting on the bicycle and its rider?

2) A car, mass m, drives over a circular hump-back bridge of radius r with a constant speed v.

When it is at the top of the bridge, what is the force on the car from the bridge?

3) A disc is rotating about an axis through its centre and perpendicular to its plane. A point P on the disc is twice as far from the axis as a point Q. At a given instant, what is the ratio of the linear velocity at P to the linear velocity at Q?

5) The maximum safe speed of a car rounding an unbanked corner is 20 m s^–1 when the road is dry. The maximum frictional force between the road surface and the wheels of the car is halved when the road is wet. What is the maximum safe speed for the car to round the corner when the road is wet?