Simple Harmonic motion problems

[ness9660]

http://sweb.uky.edu/~lsadam0/problem2.JPG


Im kinda lost on this problem. Shouldnt the Y motion be described as A*sin(wt)?

In there equation we are considering when x=0, so the kx term is removed, but where is this third term coming from, and then should Y motion just be described as Asin(-wt-o)?

[dextercioby]

Nope,unless,at t=0 the amplitude is zero.Nope,the III-rd term is called "initial phase" and should not be missing when writing the general solution.

Daniel.