Key Points from this Chapter:
We can write an equation for a wave as a function of space and time: for a 1-dimensional wave, y = f(x, t).
A sinusoidal wave, travelling to the right, can be described by a function of the form
y = Asin(2π(x-vt)/λ)
To enable us to use calculus with a function of more then one variable, we introduced the idea of a partial derivative, which is worked out with respect to one variable while others are held constant. For example, ∂y/∂x is the derivative of y with respect to variable x, while other variables are held constant.
The wave equation is a very important, second-order partial differential equation which must be satisfied by any one dimensional wave:
