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

Homework Help: How fast must a Puma leave to ground to go 12 feet high?

  1. Oct 1, 2004 #1
    This seems like an easy problem but without "time" i"m confused.

    The best leaper is a Puma that can jump to a height of 12 feet when leaving the ground at a 45 degree angle. With what speed in SI units must the Puma leave the ground to reach this height?

    I'm not sure what formula to apply since there isn't any time mentioned.
  2. jcsd
  3. Oct 1, 2004 #2


    User Avatar
    Homework Helper

    This is interesting.. because [tex] cos(45^o) = sin(45^o) [/tex] :smile:
  4. Oct 1, 2004 #3
    Do you know the formula's for the two dimensional movement under the gravity-force. You have a formule that describes the trajectory (a parabole) y = f(x). Now since the angle is 45° you can calculate all you need using this formula. There is another option when you use the x and y components for the position and velocity. Keep in mind that the y-component of the velocity is zero at the point of maximal height...

    bonne chance

  5. Oct 1, 2004 #4
    Correct. Almost always in projectiles you must consider the vertical and horizontal components of the trajectory of an object separately. You can solve this problem using marlon's hints, kinematics formulas, and physical thinking. :smile:
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook