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!

Calculating Ek At a specific point

  1. Nov 8, 2008 #1
    1. The problem statement, all variables and given/known data

    I need to find out the Ek at "B" this is the diagram i got i want to know if its right and if it is why do i use the Height of 50 to find out Ek at "B"

    [​IMG]

    2. Relevant equations

    Ek=Ep

    3. The attempt at a solution

    Ek=Ep
    Ek=m.g.h
    Ek=100x9.8x50
    Ek=49000J
     
  2. jcsd
  3. Nov 8, 2008 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF!

    Hi Articulum! Welcome to PF! :smile:
    Yes, that's right! …

    (except it's really change in Ek = change in Ep) …

    but why were you worried about using 50 for B? :smile:
     
  4. Nov 8, 2008 #3
    Re: Welcome to PF!

    If i'm figuring out Ek at "B" shouldn't i use the height also at "B"?
     
  5. Nov 9, 2008 #4
    The *change* in kinetic energy plus the *change* in potential energy equals zero here: so you do need to use the height at B, or more precisely, what matters is the *difference* in height between A and B.

    Probably the picture is badly drawn, I suppose the difference in height between A and B is 50m [the units for height are missing, too].
     
  6. Nov 9, 2008 #5
    So i use the Diffrence in height of where it starts and where the point is?
     
  7. Nov 9, 2008 #6
    Exactly!
     
  8. Nov 9, 2008 #7
    Thank you so much made my Physics work much easier
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?