1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: Work, Energy, and Power

  1. Sep 19, 2009 #1
    1. The problem statement, all variables and given/known data

    Just before striking the ground, a 200kg mass has 400J of KE. If friction can be ignored, from what heigh was it dropped

    2. Relevant equations

    KE = (1/2)mv^2
    PEg = mgh

    3. The attempt at a solution

    I drew a mass of 200kg and I drew the normal force at the top as well as the force of gravity (mg) at the bottom. My force of gravity = 9.81 and I know the KE = 400J I don't know what equation to use in order to find my height.
  2. jcsd
  3. Sep 19, 2009 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook