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!

HELP A problem on oscillation

  1. Jan 14, 2009 #1
    HELP!!!A problem on oscillation

    The problem statement, all variables and given/known data
    the equation of motion of an object is y(t)=2.0cos(0.5t+pi/4)meter
    a) Find its maximum acceleration and maximum speed, and its position at the time of these maxima.
    b) what is the speed of the object when it is +1.2m from its equilibrium position?
    c) what are the kinetic potntial and total energies at that point?


    The attempt at a solution
    a) for this part I don't reall understand what does the question mean by the maximum, is it when cos equals to 1?
    b) derive 2.0cos(0.5t+pi/4), which equals to -2sin(0.5t+pi/4)*0.5=-1sin(0.5t+pi/4)
    then plug the 1.2 into the unknown variable, which equals to -sin(0.5*1.2+pi/4)=-0.98 I don't really think it is the correct solution for this part
    c) I have to find out the correct v from part B and plug into both kinetic and potential energy equation, but I have one more problem here, which is how do i get mass for this question?
    P((1/2mv^2)i) + K(1/2mv^2)i) = P((1/2mv^2)f) + K(1/2mv^2)f)

    Thank you for helping me.
     
  2. jcsd
  3. Jan 14, 2009 #2

    LowlyPion

    User Avatar
    Homework Helper

    Re: HELP!!!A problem on oscillation

    You're given the equation for motion.

    velocity is the first derivative.

    acceleration is the second derivative.

    At what value of t then do each of these functions reach their max?
     
  4. Jan 14, 2009 #3
    Re: HELP!!!A problem on oscillation

    Sorry, but i still don't quite understand what does max mean, does it mean that when cos or sin equals to 1?
     
  5. Jan 14, 2009 #4

    LowlyPion

    User Avatar
    Homework Helper

    Re: HELP!!!A problem on oscillation

    I'd say so.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: HELP A problem on oscillation
Loading...