Homework Help: Period of a pendulum

1. Jan 25, 2006

Hootenanny

Staff Emeritus
I have already posted in the physics forum but its gone a bit quiet. Ive managed to derrive an equation up to this point. I have $$\frac{g}{L}\theta = \omega^2 \theta_{max} \sin (\omega t - \alpha)$$ and I need to prove that $$\omega = \sqrt{\frac{g}{L}}$$. I'm stuped at this one. Thank's in advance for your help.

2. Jan 25, 2006

moose

well, you need to know that it's only an approximation. It is most accurate when sinx=x (in radians of course).

3. Jan 26, 2006

Hootenanny

Staff Emeritus
That doesnt help me much all that gives then is $$\frac{g}{L}\theta = \omega^2 \theta_{max}(\omega t - \alpha)$$

4. Jan 26, 2006

Hootenanny

Staff Emeritus
Now I have $$\theta = \theta_{max} \sin(\sqrt{\frac{g}{L}} t - \alpha )$$ How Can I remove the $\alpha$ ?