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Homework Help: Inclined Surface: Velocity and angle of incline

  1. Mar 18, 2010 #1
    1. The problem statement, all variables and given/known data

    How is angle of incline related to the acceleration of the car moving down it?

    I know how to find both the velocity and acceleration of a car moving down a track using the suvat equations. I dont understand the relationship between angle of incline, velocity and gravity.

    Basically, how does increased gravitational PE affect velocity?

    2. Relevant equations


    3. The attempt at a solution

    I think it has something to do with cosine of the angle as well as 1/2mv^2

    Thank you guys and Gals!
  2. jcsd
  3. Mar 18, 2010 #2


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    Spit the weight of the car into components perpendicular to the plane and parallel to the plane.

    Also, how would you find the height the car is at when you know the length of the incline?
  4. Mar 18, 2010 #3
    i was thinking:

    mgh turns into 1/2 mv^2 (i am neglecting friction)

    rearranging gives
    v = sqroot(2gh)

    Since g is equal to acceleration due to gravity it becomes g =a*sin(angle)

    Is this correct?
  5. Mar 18, 2010 #4


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    yes but say you only had the length of the incline and the angle θ, what would h in terms of that length and θ?

    This is correct for the car's acceleration parallel to the plane
  6. Mar 18, 2010 #5
    Parallel meaning moving down the plane?

    Thanks mate!
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