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!

Speed of rocks when they hit the ground

  1. Jun 9, 2013 #1
    1. The problem statement, all variables and given/known data

    If I throw a rock upwards with an initial velocity and throw a rock downwards, what is the speed of the rocks just before they hit the ground?

    2. Relevant equations



    3. The attempt at a solution\

    They should hit the ground at the same speed and different times. I would use the conservation of mechanical energy, but someone I'm speaking to disagrees with me that they have same speed.

    How would you show this mathematically?
     
  2. jcsd
  3. Jun 9, 2013 #2

    SteamKing

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Use the formulas for objects traveling in a gravity field. You are studying physics, I presume.
     
  4. Jun 9, 2013 #3
    See your initial kinetic energy is the final potential energy.
    use this relation.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted