1. Graphing Sinusoids

2. Sinusoids
Sinusoid graphs are used to represent objects that have simple harmonic motion.

3. Definitions
Simple Harmonic Motion - If an object has vibrations, then it has simple harmonic motion.
Example – swing going back and forth
Frequency – number of cycles in a period of time(sound pitch)
Hertz – unit of measure for vibrations/second
Amplitude – distance from the center line points to the maximum/minimum points (sound volume)

4. Definitions Period – length of one cycle
Key Point Intervals – where you are going to plot the points of your sinusoid graphs
Sine: starts at center, then goes to the max amplitude, back to center, and down to min amplitude
Ex – (one cycle)
Cosine: starts at max amplitude, down to center, down to min amplitude, back to center, and back to max amplitude

5. Equation for Simple Harmonic Motion
A – amplitude
- horizontal stretch/shrink
T - time

6. Other Equations Needed
Period -
Key Point Intervals -
Frequency -

7. Graphing
To demonstrate how to graph a sinusoid, we are going to use the example equation:

8. Graphing: Step One Find Period: = = 4 Find Key Point Intervals:
Find Amp: 8

9. Graphing: Step 2
See the video on the website