1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Force of Friction and θ

  1. Oct 5, 2008 #1
    1. The problem statement, all variables and given/known data
    A box of textbooks of mass 24.0 Kg rests on a loading ramp that makes an angle θ with the horizontal. The coefficient of kinetic friction is 0.25 and the coefficient of static friction is 0.36.

    a)As the angle is increased, find the minimum angle at which the box starts to slip
    b)At this angle, find the acceleration once the box has begun to move
    c)At this angle, how fast will the box be moving after it has slid a distance 4.8 m along the loading ramp?

    2. Relevant equations

    3. The attempt at a solution
    This is pretty much the only question I'm having trouble with, b and c I can figure out once I find θ. As always any help is much appreciated.
  2. jcsd
  3. Oct 5, 2008 #2

    Doc Al

    User Avatar

    Staff: Mentor

    What forces act on the box? Just before it starts to slip, what's the net force on the box?
  4. Oct 5, 2008 #3
    the forces that act on the box are fg and fs and the net force will be zero just before it starts so.
  5. Oct 5, 2008 #4

    Doc Al

    User Avatar

    Staff: Mentor

    Good. (But don't forget the normal force.)
    Weight acts vertically; friction acts parallel to the incline. To combine forces in an equation, take components parallel to the incline.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Force of Friction and θ
  1. Friction Force (Replies: 3)

  2. Frictional Force (Replies: 6)

  3. Friction and forces? (Replies: 6)

  4. Force and Friction (Replies: 4)