Circular motionAQA A-Level Physics: Mind map

Exam questions on Circular motion

1. A stone of mass 0.15 kg is whirled in a horizontal circle of radius 0.80 m on a light string. It moves at a constant speed and completes 2.5 revolutions every second.
   Explain why the stone is accelerating although its speed is constant.2 marks
2. A car of mass 1200 kg travels at a constant speed of 18 m s⁻¹ round a flat circular bend of radius 60 m. The only horizontal force on the car is the sideways friction between the tyres and the road.
   The maximum friction force that the tyres can provide on a wet road is 8.0 kN. Calculate the maximum constant speed at which the car can take the bend.2 marks
3. A laboratory centrifuge spins sample tubes about a vertical axis at 6000 revolutions per minute. The base of each tube is 0.12 m from the axis of rotation.
   Calculate the angular speed of the tubes and the speed of the base of a tube.3 marks