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Homework Help: Finding minimum speed

  1. Oct 6, 2007 #1
    A daredevil jumps a canyon 11 m wide. To do so, he drives a car up a 15 degree incline.
    Acceleration of gravity = 9.81 m/s^2
    What minimum speed must he achieve to clear the canyon in m/s?

    2. Relevant equations

    Vf^2 = 2a(delta d) + Vi^2

    Vf = at + Vi
  2. jcsd
  3. Oct 6, 2007 #2


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    Homework Helper

    You are going to need a bit more than this to solve the problem: if there is jumping or throwing involved, you are usually going to need to look at the motion in two dimensions. What do you need to set this problem up? How do you describe where this person starts, where they're supposed to try to land, and how they traveled in between?
  4. Oct 6, 2007 #3
    Heres an idea: assume you know the velocity he took off. Now find out how far he traveled. Create an equation for it to only be in terms of his initial velocity, distance traveled and other constants. Then work backwards from here and find his velocity knowing how far he has to travel.
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