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Kinetic energy dissipation by friction

  1. Feb 17, 2012 #1

    Is the equation right ? How do i solve it ?

    Thanks in advance and sorry about my poor english or something else
  2. jcsd
  3. Feb 17, 2012 #2

    Doc Al

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    Staff: Mentor

    Not really. That's not a force equation, but an energy balance one. By setting up such an energy balance equation, you could solve for the distance traveled. But that's not what's asked for.

    Instead, solve for the acceleration.

    What's the force of friction?
  4. Feb 17, 2012 #3
    It is infact just a Kinematics 1D Problem. The body undergoes a constant retardation due to friction. So just use v = u + at .
  5. Feb 17, 2012 #4
    hmm i formulated wrong. If the friction coeficient "u" is a nonlinear function, lets say, u = x^2 how it would be solved ?
  6. Feb 17, 2012 #5
    Write force equation and solve the differential Equation.

    We'll have [itex]m\cdot \frac{dv}{dt} = \mu mg \implies v dv =k x^2g dx[/itex], Since [itex]\mu = kx^2[/itex]
  7. Feb 17, 2012 #6
    Thank you very much for the help, you people are right and its a question about aceleration.

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