Centripetal Force & the Road. Learning Objectives. Book Reference : Pages 26-27. Centripetal Force & The Road. To show that the centripetal force is provided by real world forces such as tension, gravity & friction To consider three particular cases of motion:
Centripetal Force & the Road
Book Reference : Pages 26-27
Centripetal Force & The Road
During the last lesson we saw that an object moving in a circle has a constantly changing velocity, it is therefore experiencing acceleration and hence a force towards the centre of rotation.
We called this the centripetal force: The force required to keep the object moving in a circle. In reality this force is provided by another force, e.g. The tension in a string, friction or the force of gravity.
Centripetal Acceleration : Recap
Consider a car with mass m and speed v moving over the top of a hill...
Over the top 1
Over the top 2
On a level road, when a car travels around a roundabout the centripetal force required to keep the car moving in a circle is provided by the friction between the road surface and tyres
Around a Roundabout 1
Force of Friction F
F = mv2 / r
Around a Roundabout 2
For high speed travel, race tracks etc have banked corners. In this way a component of the car’s weight is helping friction keep the car moving in a circle
Banked Tracks 1
Towards centre of rotation
Banked Tracks 2
Banked Tracks 3