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

Deriving the work-energy theorem

  1. Jun 19, 2005 #1
    In this problem, you will use your prior knowledge to derive one of the most important relationships in mechanics: the work-energy theorem. We will start with a special case: a particle of mass m moving in the x direction at constant acceleration a. During a certain interval of time, the particle accelerates from v_initial to v_final, undergoing displacement s given by s=x_{\rm final}-x_{\rm initial}.

    the problems asks me to find the acceleration :Find the acceleration a of the particle.
    Express the acceleration in terms of v_initial, v_final, and s.
    this is my answer: (v_final-v_initial)^2/s

    but it says that: Your answer is close. One problem with your answer is that it is always positive, but acceleration can also be negative. ?
  2. jcsd
  3. Jun 19, 2005 #2


    User Avatar
    Homework Helper

    Look at the units, and remember acceleration is the change in velocity per unit time.
  4. Jun 19, 2005 #3

    Doc Al

    User Avatar

    Staff: Mentor

    Your answer is incorrect. Show how you arrived at it.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook