# What is Amplitude?

Nov 6, 2014

"(Amplitude)"=1/2["(Highest Value)"-"(Lowest Value)"]

graph{4sinx [-11.25, 11.25, -5.62, 5.625]}

In this sine wave the highest value is $4$ and the lowest is $- 4$

So the maximum deflection from the middle is $4$k.

This is called the amplitude

If the middle value is different from $0$ then the story still holds
graph{2+4sinx [-16.02, 16.01, -8, 8.01]}

You see the highest value is 6 and the lowest is -2,
The amplitude is still $\frac{1}{2} \left(6 - - 2\right) = \frac{1}{2} \cdot 8 = 4$