Wave notes

NOTES - THERE ARE 3 COMPLETE WAVES IN THE IMAGE ABOVE.

Frequency (f) - number of waves per second (in hertz, Hz)

Wavelength (l - this should really be lambda, the Greek symbol) - the length of one wave.  It can also be thought of as the distance between 2 crests, 2 troughs or the distance from the start to finish of ONE wave.

Speed (v) - literally (in m/s), how fast one wave is traveling (relative to some background)

These 3 variables are related by this equation:

v = f l

That is, speed equals frequency times wavelength.  With light waves, the speed is constant - it's the speed of light in a vacuum (3 x 10^8 m/s, or 186,000 miles/second). 

Since the speed is constant, as the wavelength goes UP, the frequency goes DOWN.  Or the other way around, if the frequency goes UP, the wavelength goes DOWN.