1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    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!

Elastic Potential Energy and spring

  1. Feb 4, 2009 #1
    A 2.40 kg object is hanging from the end of a vertical spring. The spring constant is 40.0 N/m. The object is pulled 0.200 m downward and released from rest. Complete the table below by calculating the translational kinetic energy, the gravitational potential energy, the elastic potential energy, and the total mechanical energy E for each of the vertical positions indicated. The vertical positions h indicate distances above the point of release, where h = 0

    I have already found kinetic and gravitational potential energy. I need to find elastic potential energy at h=0, .2, and .4m

    Elastic Potential Energy= .5kx squared

    .5(40)(.2)squared= .8 J

    .8 J is the incorrect answer, but i know .5kx squared is the right equation... what am I doing wrong?!?!

    At this height (.2 above the release point) I found the correct kinetic energy to be .81 J and the correct gPE to be 4.7088 J
    Last edited: Feb 4, 2009
  2. jcsd
  3. Feb 4, 2009 #2


    User Avatar
    Homework Helper

    I'm confused over the point of release and the equilibrium point.
    Looks to me like the point of release is h = 0, x = -0.2.
    So at h = 0.2, x = 0 and the Elastic PE = 0.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Elastic Potential Energy Date
Elastic Potential Energy Jun 18, 2017
Elastic and gravitational potential energy Nov 15, 2016
Motion with elastic potential energy and other forces May 30, 2016
[Mechanics] Tension in bungee jumping Apr 24, 2016