sarah786 2 years ago A cyclist cycling around a circular racing track skids because A.the centripetal force upon him is less than limiting friction B.the centripetal force upon him is greater then limiting friction C.the centripetal force upon him is equal to the limiting friction D.the friction between the tyres of the cycle and road vanishes

1. sarah786

@AllTehMaffs :)

2. AllTehMaffs

Which one do you think?

3. AllTehMaffs

hai

4. AllTehMaffs

|dw:1382088401350:dw| Which way would the cyclist slide, and what are the two forces working against each other?

5. AllTehMaffs

:)

6. sarah786

Centripetal and Centrifugal forces :/

7. sarah786

is it B ?

8. AllTehMaffs

1/2 of that is right:) That half is 100 % right. Centripetal force pushing towards the center of the circle, and it's the friction that's applying the force. I drew the first diagram wrong. |dw:1382107001459:dw| The sum of all the forces is equal to the centripetal force $\sum F = F_f =m a_c = F_c$ I think I may have explained that poorly ;/ Centrifugal force doesn't really exist. The thing people call "centrifugal" force is just the tendency of your body to keep going straight while the car is turning. That's another question though :)

9. sarah786

its B then ???

10. AllTehMaffs

Yup yup :) $a_c = \frac{v^2}{r}$ so if $F_c > F_f$ the bike skids.

11. sarah786

ty so much :)