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Homework Help: Projectile Motion skydiver

  1. Oct 8, 2011 #1
    1. The problem statement, all variables and given/known data
    A skydiver deploys his parachute when he is 860 m. directly above his desired landing spot. He then falls through the air at a steady 5.8 m/s . There is a breeze blowing to the west at 2.0 m/s. At what angle with respect to vertical does he fall? By what distance will he miss his desired landing spot?


    2. Relevant equations
    xf=xi+Vxi*t
    yf=yi+Vyi*t-1/2*g*t^2


    3. The attempt at a solution
    I was able to find the angle by finding the tan^-1=71, and then 90-71=19
    However, I completely stucked with the second answer. I was going to find first t:
    0=860m+5.8m/s*t-1/2*9.8m/s^2*t^2
    and then xf=2.0m/s*t but apparently that's the wrong answer. I guess the mistake is somewhere in the equations...Please, can you help me out? Thank you so much!
     
  2. jcsd
  3. Oct 8, 2011 #2

    PeterO

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    Homework Helper

    The parachutist is not really undergoing projectile motion - he is merely descending at constant speed.

    When calculating his descent time, there is no reference to g (9.8) as his parachute eliminates it.
     
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