1) A racing car of mass 500 kg, including driver but not fuel, decelerates from a speed of 50 m s^-1 to 30 m s^-1 when approaching a bend.

The brakes exert a fixed retarding force of 7000 N. The time for the car to decelerate when it is almost out of fuel is t₁. The time for it to decelerate when it has a full load of 130 kg of fuel is t₂.

What is the difference (t₂ – t₁) in the two timings?

2) In deep outer space, there is no gravity. If a force acts on an object, it will gain a great speed after some time.

What is the speed of a 100 g mass if a force of 2.0 N acts on it for 2 days?

The mass is initially at rest.

3) A block of mass 20 kg is moving with a velocity of 5.0 m s^-1. What is the force required to stop the block in 2.0 seconds?

4) A heavy sack is suspended from a ceiling by a rope.

The sack is pulled to one side and held stationary.

Which diagram represents the forces acting on the sack in its new position?

5) 2023 S3 EOY P1 Q20

An object of mass 4.2 kg weighs 16.0 N on an unknown planet.

What is the gravitational field strength on that planet?