1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: Friction on Inclined Plane

  1. Nov 5, 2011 #1
    1. The problem statement, all variables and given/known data
    On Mountain roads, ramps of gravel are constructed to allow trucks that have lost their brakes to come to a stop. Suppose a 15,000kg truck hits one of these ramps at 35m/s. The incline of the ramp is 6 degrees and the coeffiecent of friction is 0.40.
    By using work and energy it is asked to find the distance the truck travels along a ramp.

    2. Relevant equations
    K= 1/2 m*v2

    3. The attempt at a solution

    I calculated K to be -9187500 and U to be 147150*h
    W= ΔK + ΔU
    Then tired to use W=F*d cos6
    But got stuck with that height.
    I can't use trig fuctions to find my h because the distance is what im trying to find....
  2. jcsd
  3. Nov 5, 2011 #2
    You can use trigonometry to solve for the distance. Recall that [itex] d^{2} = x^{2} + h^{2} [/itex] and that [itex] x = d cos \theta[/itex] [itex]h = d sin \theta [/itex] . Once you find either x or h you can solve for d.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook