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: Find the work done by nonconservative forces in stopping the plane.

  1. Sep 27, 2010 #1
    1. The problem statement, all variables and given/known data
    Find the work done by nonconservative forces in stopping the plane.

    A 18000 {\rm kg} airplane lands with a speed of 92 {\rm m/s} on a stationary aircraft carrier deck that is 115 {\rm m} long.


    2. Relevant equations
    W = FD


    3. The attempt at a solution

    18000 * 92 * 115 = 190440000 J

    Unless it's wanting 1.9 * 10^8 = 190000000 J (which seems wrong since detail is lost)

    (I don't think that's 2 significant digits.)
     
  2. jcsd
  3. Sep 27, 2010 #2

    berkeman

    User Avatar

    Staff: Mentor

    The best way to solve this type of problem is with energy considerations. What was the KE of the plane just before it traps on the carrier deck? What is the KE right after it is stopped by the wire? Wher did that energy go?
     
  4. Sep 27, 2010 #3
    it was 1/2(m)(v)^2 or something.

    The answer was -7.6 x 10 ^7

    Thanks!
     
  5. Sep 27, 2010 #4

    berkeman

    User Avatar

    Staff: Mentor

    Does that mean that you calculated the correct answer? What are the units of the answer?
     
  6. Sep 28, 2010 #5
    Yes, the units of the correct answer was in joules.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook