Just started Centripetal Force

1. Jul 12, 2008

HelloMotto

ok the textbook says Centripetal Force always points towards the centre of circle as well as the Centripetal acceleration. But Why?

Also I was given a diagram in the textbook like the one below. I dont understand why
Fc = the friction force...

could you guys explain this to me please?

2. Jul 12, 2008

Kurdt

Staff Emeritus
The force must always point toward the centre of a circle to keep the particle or object moving round in a circle. I don't know why the centripetal force equals the friction force, it depends on the context. Could you give more information?

3. Jul 12, 2008

HelloMotto

thank you.
that diagram i posted comes from a question related to car that is rounding a curve on a level road.

4. Jul 12, 2008

Kurdt

Staff Emeritus
In that case the centripetal force will equal the static friction when the car is going round the curve at a speed just before slipping. If you go round a curve too fast the friction will not be enough to keep the car from sliding and you will skid off.