Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Projectile motion equation help

  1. Aug 6, 2005 #1
    This question was on my last test, and I got it wrong. If anyone could help me understand how to get the answer, I would really appreciate it!

    A small metal ball with a mass of m = 91.7 g is attached to a string of length
    l = 1.57 m. It is held at an angle of q = 47.5° with respect to the vertical.
    The ball is then released. When the rope is vertical, the ball collides head-
    on and perfectly elastically with an identical ball originally at rest. This
    second ball flies off with a horizontal initial velocity from a height of h =
    3.19 m, and then later it hits the ground. At what distance x will the ball

    I'm not even really too sure on how to approach it!
  2. jcsd
  3. Aug 6, 2005 #2
    you would use projectile motion on this one as well as angular acceleration.

    ar = v^2 / r

    the range of the projectile isd given by
    R = (v062 * sin (2 theta)) / g
  4. Aug 6, 2005 #3
    Thanks a lot for the help, but is there anything else you can tell me. What's throwing me off is that I'm not sure how to find the velocity. I feel like i'm overlooking something simple :confused:
  5. Aug 6, 2005 #4
    first you would use the equation

    a = g sin (theta)

    then intergate to find vel
  6. Aug 6, 2005 #5
    Got it, thanks so much!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook