# Quick wave question

1. Dec 8, 2005

### Nm

Can someone tell me how to find the intensity given only the wavelength in meters and amplitude in Pascals? Thanks.

2. Dec 9, 2005

### Nm

Does anyone know?

I found the frequency, but I'm a bit confused about why amplitude is in Pascals and how I would find the intensity.

3. Dec 9, 2005

### dimensionless

The intensity in dB is
$$I = 20 log_{20} \left[ \frac{P}{P_{0} \right]$$
Where $$P$$ is the pressure of the wave in pascals and $$P_{0} = 2x 10^{-5} \frac{N}{m^2}$$.

Actually I've got a conflicting source that says "Intensity is a measure of the sound energy that passes through a given area each second."

Last edited: Dec 9, 2005