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Homework Help: Ski jump problem

  1. Jun 19, 2010 #1
    1. The problem statement, all variables and given/known data
    A ski jumper leaves the end of the slope, make a 35º with the horizontal and the slope making -45º with the horizontal. it has initial velocity of 8m/s. For him not to fall the tangent of the trajectory and the slope at the moment of impact should not be bigger then 20º, please verify if thats the case

    2. Relevant equations
    x = 8*cos(35)t
    y = 8*sen(35)t -(1/2)gt^2

    I have this exercise solved, what i'm trying to understand is why we want that y = -x, everything in pink is not in the original "drawing" of the problem

    new here so hello everyone ^^

    Attached Files:

  2. jcsd
  3. Jun 19, 2010 #2
    Welcome to the forums.

    The reason why you want y = -x is to do with the fact that they specifiy when horizontal and the slope making -45º with the horizontal. Try drawing yourself a right angled triangle where one of the angles is 45º, by doing so the other one must be 45º, and both non hypotenuse sides are equal in length.

    Can you see why this implies y = -x ?
  4. Jun 19, 2010 #3
    Oh ok, took a while to realize that, i guess my own drawing was misleading me, (cause i do a curve for the slope). Now i can see the relation that implies y = -x

    so its something like whats in purple in the new picture.

    Thanks ^^

    Attached Files:

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