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Projectile Motion - Please help, Im struggling!

  1. Apr 12, 2008 #1
    1. The problem statement, all variables and given/known data
    A object is projected with a velocity of 100 m/s at an elevations 30 degrees from a tower 150m high.

    a) Time of flight
    b) The horizontal distance from the tower at which the stone strikes that ground.
    c) The magnitude and the direction of the velocity of the stone striking the ground.

    2. Relevant equations
    v^2 = u^2 + 2ax
    3. The attempt at a solution


    50.2=100 -10t
    t1= 5.02s
    t2 = 5.02s

    Am I on the right track at all?

    Attached Files:

  2. jcsd
  3. Apr 12, 2008 #2
    what are these t1 t2 and t3 ?
    If you have the book PHYSICS by Resnic and Haliday please look in it for the solution.
  4. Apr 12, 2008 #3
    You have some help https://www.physicsforums.com/showthread.php?t=227924".

    For the (a) part you have vertical shot (y component of the velocity) and then free fall from the height of 150 m at initial velocity of [tex]v_{y}=v_{0}sin\alpha.[/tex]

    For the (b) part you need the x component. You have the time from the (a) part, so it's pretty easy.

    (c) part is also simple. You need the net velocity (trigonometry). X component doesn't change but the y component is increased by gravity.
    Last edited by a moderator: Apr 23, 2017
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