Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Circular motion

  1. Apr 21, 2008 #1
    1. The problem statement, all variables and given/known data

    A toy with a mass of 100g is going through a loop-the-loop with a diameter of .5m. How fast must the car be moving at the top of the loop in order to not fall.

    3. The attempt at a solution

    At the top of the loop, there is a normal force (Fn) and the force of gravity (Fg). I'm not sure how to do this. Do I neglect one of the forces? Set one to zero, or what?
  2. jcsd
  3. Apr 21, 2008 #2

    Doc Al

    User Avatar

    Staff: Mentor

    What happens to the normal force when the car is just about to lose contact with the track?
  4. Apr 21, 2008 #3
    Fn approaches 0. Thanks.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook