Uniform Circular Motion of a motorcycle

[ShamTheCandle]

Homework Statement

A motorcycle has a constant speed of 25.0 m/s as it passes over the top of a hill whose radius of curvature is 126 m. The mass of the motorcycle and driver is 342 kg. Find the magnitude of (a) the centripetal force and (b) the normal force that acts on the cycle.

Homework Equations

F(centripetal) = mv^2/r
Weight=mg

The Attempt at a Solution

Using the formula for centripetal force, I found that the answer for part (a) is 1.70 x 10^3 N. My answer matches with the back of book. So it is right. However, for part (b) I used that
Normal Force = Weight + Centripetal Force = 5048 N. I don't think it is right since the back of the book says the answer is 1.66 x 10^3.

Thank you for helping.

 

[thefifthlord]

Centripetal force always acts towards the center, in this case the center is up, so its actually
Edit: Sorry typo.
Fn = Fg - Fc

To anyone who is reading this thread, i need major help here: https://www.physicsforums.com/showthread.php?t=356807

 

[ShamTheCandle]

Centripetal force always acts towards the center, in this case the center is up, so its actually
Edit: Sorry typo.
Fn = Fg - Fc

To anyone who is reading this thread, i need major help here: https://www.physicsforums.com/showthread.php?t=356807

Ohhh, I see. This makes sense now. Thank you!