Damper Oscillator dropping amplitude to half the original value

[Hypnos_16]

Homework Statement

Consider a damped oscillator
Assume that the mass is 318g, the spring constant is 104 N/m, and b = 0.106 kg/s. How long does it take for the amplitude to drop to half its initial value?

M = 318 g Or 0.318 kg
K = 104 N/m
b = 0.106 kg/s

Homework Equations

n / a

The Attempt at a Solution

I have no sweet clue how to even start something like this! Help would be greatly appreciated!

 

[Spinnor]

Can you understand the first two pages of this:

http://www.scar.utoronto.ca/~pat/fun/NEWT1D/PDF/OSCDAMP.PDF

Do you have a textbook? If not see:

http://www.google.com/search?hl=en&...&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi

and this,

http://www.google.com/webhp?hl=en#h..._gc.r_pw.&fp=2a7474386fcf4d4e&biw=838&bih=474

 

[danielakkerma]

Do you know the equations of (damped) oscillatory motion?
Have you tried solving:
$a\ddot{x}(t)+b\dot{x}(t)=-cx(t)$?
I'd refer you hither, and you can simply plug in if you like, but I recommend actually solving for the general case, it's fairly trivial, and very instructive...
http://en.wikipedia.org/wiki/Harmonic_oscillator#Damped_harmonic_oscillator"
Daniel