# How are a wave's energy and amplitude related?

##### 1 Answer

Intensity,

For a point source of a wave the energy is distributed across an area equal to the surface area of a sphere with a radius equal to the distance from the receiving location to the point source:

**Extending #IpropA^2#**

If

So

That is useful for calculating intensity or amplitude ratios given enough information to determine the other ratio.

A more general relationship that you can see from the intensity equation above is

You can then also see the relationship between amplitude and distance: