1. Frequency
Higher frequency = high sound = More waves = shorter wavelength
Low frequency = Low sound =Less waves= longer wavelength

2. Period of a Wave
The period is the duration of one cycle in a repeating event.
Frequency is a measure of the number of occurrences of a repeating event per unit time.

3. Vibrations Sound is caused by vibrations
Sound requires a medium (does not happen in outer space since it is a vacuum.)
Sound will travel through water at 20 degrees Celsius slower than water at 80 degrees Celsius.

4. Energy
The amount of energy a wave has determines it’s amplitude.

5. Sound The unit used to measure sound intensity is the decibel.
Pitch is how high or low a sound seems to be.
When a person moves toward a sound, the compressions of the wave are pushed together.

6. Frequency
The frequency at which a string vibrates is its natural frequency
The frequencies of an instrument’s tone that are multiples of the fundamental frequency are overtones.

7. Instruments
Brass and wind instruments make sounds by vibrating a column of air.
Beats are produced by 2 sound with different frequencies

8. FM
FM broadcasting is a broadcast technology invented by Edwin Howard Armstrong
FM carrier wave frequencies vary from 88 Mhz to 108 Mhz
FM = Frequency Modulation

9. Radio
Each radio station broadcasts on one frequency called a carrier wave.
Information can be added to a radio carrier wave by frequency modulation and amplitude modulation.

10. Sound Violins, harps, and guitars produce sound by vibrating strings.
A flute player changes the length of a column of air by opening and closing holes which helps make each different sound.

11. Formulas

12. Formula Practice The frequency is 30. What is the period of the wave.
1/30
The period is 10, what is the frequency of the wave?
1/10