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!

Work,Energy and Power

  1. May 29, 2016 #1
    1. The problem statement, all variables and given/known data
    A body of mass 2 kg thrown vertically with KE of 490 joules. If the acceleration due to gravity is 9.8 m/s^2 of the body becomes half its original value is given by:

    a.50
    b.12.5
    c.25 m
    d.10 m

    2. Relevant equations
    PE=MGH
    K.E=1/2MV^2
    PE=KE
    3. The attempt at a solution

    K.E=P.E
    490=MGH
    490=2*9.8*H
    490=19.6*H
    490/19.6=H
    25=H
    H=25 m

    is it right ? or we have to half the value.
     
  2. jcsd
  3. May 29, 2016 #2

    jbriggs444

    User Avatar
    Science Advisor

    What is the question? The second sentence is incoherent. My best guess is that it is asking how high the body needs to go to lose half of its kinetic energy due to gravity.

    In that case, the Kinetic Energy that is lost and the Potential Energy that is gained are both half of 490 joules.
     
  4. May 29, 2016 #3
    yes sorry the sentence is . "the height at which the K.E of the body becomes half its original value is given by"
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Work,Energy and Power
  1. Energy, Work, and Power (Replies: 10)

  2. Work, Power and Energy (Replies: 2)

  3. Work energy and power. (Replies: 8)

Loading...