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: Wave on a string problem

  1. Feb 5, 2008 #1
    1. The problem statement, all variables and given/known data

    If y(x,t)=(6.0mm)sin(kx+(600rad/s)t+[tex]\Phi[/tex]) describes a wave travelling along a string, how much time does any given point on the string take to move between displacements y= +2.0mm and y= -2.0mm?

    2. Relevant equations

    I think y(t)=ym sin([tex]\omega[/tex]t) ?

    3. The attempt at a solution

    well if I plug in 2.0mm for y, 6.00mm for ym and 600rad/s for [tex]\omega[/tex] I come up with the equation 2.0mm=6.00mm sin (600rad/s * t). Where do I go from here? are my assumptions correct so far?

    Other things as I am thinking- 600rad/s is about 95.5Hz so each complete cycle from +6mm to -6mm should take .01s or so, so my answer should be less then that.

    Thanks for your help
    Last edited: Feb 5, 2008
  2. jcsd
  3. Feb 5, 2008 #2
  4. Feb 5, 2008 #3
    I think I have it- if I then take



    then [tex]\Delta[/tex]T is T1-T2?

    does anyone have any input here?
  5. Feb 5, 2008 #4
    pretty sure I've got it-











    do the math and [tex]\Delta[/tex]t is .00113s

    I think this is solved
  6. Jul 27, 2009 #5
    no one ever responded to this guys problem, and now i'm actually trying to solve this as well and i tried doing the method he ended up using but i am not getting a correct answer. Although his method for the most part looks right and makes sense to me, the only thing I figure would be the problem is that x isn't a constant so they should cancel i don't think....but i'm not sure what else to do with so many unknown variables...any help???
  7. Jul 27, 2009 #6
    oops nevermind...my calculator was in degree mode instead of radian mode
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook