**1. The problem statement, all variables and given/known data**

The equation for a damped oscillation is [tex]y(t)=Ae^{-\frac{b}{2m}t}cos(\omega’t + \phi)

[/tex]

We know that y(0)=0.5 and y'(0)=0.

Find the values of A and ø and then plot the oscillation in MATLAB.

**2. Relevant equations**

See above

**3. The attempt at a solution**

When derivating y(t) we get

[tex]y'(t)=Ae^{-\frac{b}{2m}t}(-\frac{b}{2m}cos(\omega’t+\phi)-\omega’sin(\omega’t + \phi))[/tex]

This, together with the initial values gives that [tex]A=\frac{1}{2cos(\phi)}[/tex] and [tex]\phi=arctan(-\frac{b}{2m\omega’})[/tex]

Is this correct? If not, then what is wrong?

http://ift.tt/1ic4J7R