1. Harmonic Motion

2. Harmonic Motion Moving things have two different kinds of motion
Linear Motion
Harmonic Motion

3. Harmonic Motion Linear Motion Goes from one place to another
without repeating
Involves the concepts of distance,
time, speed, and acceleration

4. What are some examples of Linear Motion?
Harmonic Motion
What are some examples of Linear Motion?

5. Harmonic Motion Harmonic Motion Repeats itself over and over
Caused by a restoring force.
Ex: pendulums, bouncing springs,
wheels, waves, and music.

6. Harmonic Motion Restoring Force A force that tries to return an object
to equilibrium (center resting
position)
When you move a pendulum gravity
is the restoring force pulling it
back to center.

7. Cycles, Systems, and Oscillators
Harmonic Motion
Cycles,
Systems,
and Oscillators

8. Harmonic Motion Cycle Is the building block of harmonic motion
It is a unit of motion that repeats itself
over and over with a set series of
events

9. Harmonic Motion Cycle A cycle has a beginning and an ending
The cycle has to include all the
motions that repeat

10. The cycle of the pendulum is defined by where we choose the beginning
Harmonic Motion
The cycle of the pendulum is defined by where we choose the beginning

11. Harmonic Motion Systems A system is a group we choose that
includes all things we are interested in
Choosing a system helps us
concentrate on what is important and
exclude what is not important

12. Harmonic Motion
If you constructed a pendulum for a lab, what would you include in the system and what would you exclude from it?

13. Harmonic Motion Oscillator Is a system that shows harmonic motion
Ex: an atom, your heart and the
muscles that surround it, the
solar system

14. Harmonic Motion From Oscillations comes: Light Sound Music Color
Communications
Timekeeping

15. Harmonic Motion Period Is the length of time for one cycle; how
long it takes for one repetition

16. Harmonic Motion Frequency The unit of measurement is hertz (Hz)
Is closely related to period
In an oscillator, frequency is the number
of cycles it makes per second
The unit of measurement is hertz (Hz)
A frequency of one cycle per one
second is one hertz

17. Harmonic Motion
Frequency and period are inversely related. The period is the time per cycle. The frequency is the number of cycles per time

18. Harmonic Motion
Ex: Calculate the frequency of a pendulum that has a period of ¼ second.
Formula for frequency is F=1/T
F = 1/ (0.25 sec)
= 4 Hz

19. Harmonic Motion Amplitude Is the maximum distance or angle
the motion moves from its center
position.
Can be measured in distance or
degrees

20. Harmonic Motion
Amplitude

21. Harmonic Motion Amplitude Measuring amplitude
It is the maximum distance the
motion moves away from the
center.

22. Harmonic Motion A pendulum with an amplitude of 20 degrees
swings 20 degrees
away from the center