Simple: Finding the wavelenght

[StotleD]

I have a picture of a wave I am looking at. Each increment on the equilibrium line is 420 cm. I am asked to find the wavelength. there are 7 increments between one location of the first wave and the second wave. I multiply 7 times 4.2 meters and the answer is still wrong. Why?

[Nylex]

What do you mean by "each increment on the equilibrium line"?. I don't really understand your description. Do you have a graph of a wave or something? The wavelength is just the distance from one peak to the next, or one trough to the next. Edit: it doesn't necessarily have to be peak to peak, for example, but it's just easier to see it if you take it as that.

[StotleD]

Thank you Nylex, but that was the first thing I did. I am still getting a "incorrect answer". Yes, I am looking at a picture of a wave. I though I was dong something wrong so I multiplied the number of increments times the given lenght. Am I wrong or am I missing a step?

[Nylex]

What do you mean by "increments"? :confused: