Physics Questions of the Day?

Question

I need help working these out. I have all the answers but it doesn't help when I don't know how they got them.

A roller coaster at an amusement park has a dip that bottoms out in a vertical circle of radius r. A passenger feels the seat of the car pushing upward on her with a force equal to twice her weight as she goes through the dip. If r = 20.0 m, how fast is the roller coaster traveling at the bottom of the dip?

Answer 1

This is a centripetal acceleration problem.

Acent= g
Acent=v^2/r
v^2=g*r
v=14 m/sec

good luck

Remo