1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Help with projectile motion-type question

  1. Jan 31, 2007 #1
    1. The problem statement, all variables and given/known data

    A 507.0 g model rocket is resting horizontally at the top edge of a 40.0 m high wall when it is accidentally bumped. The bump pushes it off the edge with a horizontal speed of 0.630 m/s and at the same time causes the engine to ignite. When the engine fires, it exerts a constant 24.1 N horizontal thrust away from the wall. How far from the base of the wall does the rocket land?

    I don't know where to start - I am not asking for the answer, just some direction on where to start...

    If anyone could help me on this, it would be fantastic. I am pretty much stumped! Thanks!
    Last edited: Jan 31, 2007
  2. jcsd
  3. Jan 31, 2007 #2
    well being a rocket nut I can't resist, but at the same time the problem is poorly stated IMO. I'm assuming the rocket engine is firing horizontal/edit never mind missed that part.

    (However that will not remain so, as the rocket "weathercocks" so the nose is pointed increasingly downward, but I doubt that is intended for consideration)

    so set up two velocities as a function of time: one in the x direction, given the initial velocity plus that acceleration privided by the motor and the other in the y. You can figure the time it hits the ground from the latter, ie a bullet shot horizontally from a rifle in theory should hit the ground at the same time as a bullet simply dropped from the height of the barrel. Does that help a little?
    John S
    Last edited: Jan 31, 2007
  4. Jan 31, 2007 #3
    How would you solve this if there was no rocket acceleration in the x?
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Help with projectile motion-type question