# Math Help - Springs

1. ## Springs

Ok so these is no example in my book on how to do this and i missed this day of class. I understand how to get to a general equation of something like this but i don't know how to do the reverse. The problem is:

The equation of motion of a spring-mass system is given by

$y(t)=e^{-3t}[-2cos(5t)+sin(5t)]$

Determine the corresponding standard damped amplitude-phase lag expression for $y(t)$.

I can't find that phrase "amplitude-phase lag" any where in my text so i have no idea what he's asking for. Can anyone give a little help? Thanks alot ^.^

2. Originally Posted by mortalapeman
Ok so these is no example in my book on how to do this and i missed this day of class. I understand how to get to a general equation of something like this but i don't know how to do the reverse. The problem is:

The equation of motion of a spring-mass system is given by

$y(t)=e^{-3t}[-2cos(5t)+sin(5t)]$

Determine the corresponding standard damped amplitude-phase lag expression for $y(t)$.

I can't find that phrase "amplitude-phase lag" any where in my text so i have no idea what he's asking for. Can anyone give a little help? Thanks alot ^.^
It's a bit over my head, but here's a reference on the web:

http://ocw.mit.edu/NR/rdonlyres/Math...0FDD/0/c18.pdf

see how you get on