Centripetal Acceleration Problem HELP

[Sucks@Physics]

I don't know what I'm doing wrong on this one...

What is the centripetal acceleration of a point on the perimeter of a bicycle wheel of diameter 70cm when the bike is moving 7.0m/s.

isn't centripetal acceleration just v^2 / r?

I get 140m/s^2, but the answer is 180m/s^2

 

[pinkyjoshi65]

did you convert 70 cm into metres? And also 70 cm is the diametre, to get the radius you hve to divide the Diametre by 2..

 

[Sucks@Physics]

yea i did. .35 = radius 7=velocity 7^2/.35 = 140m/s^2