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: Derive the equation

  1. Oct 4, 2013 #1

    Marcsmeets

    User Avatar

    1. The problem statement, all variables and given/known data

    Derive the equation v^2 = u^2 + 2as

    I have no clue how to do this please can someone help!

    Thank you!
     
    Marcsmeets, Oct 4, 2013
  2. jcsd
    Phys.org - latest science and technology news stories on Phys.org
  3. Oct 4, 2013 #2

    barryj

    User Avatar

    Notice that there is no t involved in this relationship. Look at your equations for distance and average acceleration and see how to eliminate t.
     
    barryj, Oct 4, 2013
  4. Oct 4, 2013 #3

    gneill

    User Avatar

    Staff: Mentor

    I don't know about you, but whenever I see velocity-squared terms I tend to think about kinetic energy... :wink:
     
    gneill, Oct 4, 2013
  5. Oct 4, 2013 #4

    barryj

    User Avatar

    gneill, I am sure you are correct but you can also derive this equation from two basic equations and energy principals are not required.
     
    barryj, Oct 4, 2013
  6. Oct 4, 2013 #5

    gneill

    User Avatar

    Staff: Mentor

    Sure. But it's nice to have options. Some approaches are more intuitively obvious to different people.
     
    gneill, Oct 4, 2013
  7. Oct 4, 2013 #6

    barryj

    User Avatar

    If you use energy, then you have to introduce mass and this is not necessary.
     
    barryj, Oct 4, 2013
  8. Oct 4, 2013 #7

    gneill

    User Avatar

    Staff: Mentor

    Mass disappears by cancellation. No biggie. Or use specific energy :smile:
     
    gneill, Oct 4, 2013
  9. Oct 4, 2013 #8

    barryj

    User Avatar

    So why complicate a simple problem?
     
    barryj, Oct 4, 2013
  10. Oct 4, 2013 #9

    gneill

    User Avatar

    Staff: Mentor

    It's no more complicated an approach if you're familiar with the concept. Like I said, different strokes for different folks.

    Let's wait to see what the OP comes up with.
     
    gneill, Oct 4, 2013
  11. Oct 4, 2013 #10

    IamBatman

    User Avatar

    Derive via using other kinematic equations?
     
    IamBatman, Oct 4, 2013
  12. Oct 4, 2013 #11

    Mandelbroth

    User Avatar

    Note that this equation is assuming that acceleration, the derivative of velocity with respect to time, is constant. This is, then, just a simple exercise in calculus.
     
    Mandelbroth, Oct 4, 2013
  13. Oct 4, 2013 #12

    Chestermiller

    User Avatar
    Insights Author

    Staff: Mentor

    Hi Marksmeets. Welcome to Physics Forums. We can best answer your question if we know whether you have had calculus yet. Have you?
     
    Chestermiller, Oct 4, 2013
  14. Oct 4, 2013 #13

    IamBatman

    User Avatar

    I'm thinking if its an intro class then there's no calculus and just want you to use other kinematic equations to this one. I remember having a question where it was just that for intro physics but I can't be certain about op.
     
    IamBatman, Oct 4, 2013
  15. Oct 4, 2013 #14

    barryj

    User Avatar

    This is definitely an intro physics question. Only algebra 1 is needed, that is if you have the two kinematic equations.
     
    barryj, Oct 4, 2013
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted