1. 11/30/15
Ch. 17 Mechanical Waves
Day 1

2. Objectives
SWBAT explain the difference between the two MAIN types of waves
SWBAT describe the anatomy of a wave and how it applies to transverse waves

3. A rhythmic disturbance that carries energy. (NOT MATTER!!)
A WAVE is…
A rhythmic disturbance that carries energy.
(NOT MATTER!!)

5. Electromagnetic (EM) Waves
Also called the Electromagnetic (EM) Spectrum
DOES NOT require a MEDIUM (matter or material) to travel
CAN TRAVEL through space

6. Mechanical Waves
A rhythmic disturbance that carries energy through a medium (ex. water, air, soil and rock)
MUST HAVE a MEDIUM to travel

7. Transverse Waves Matter travels perpendicular to the wave
WAVE MOTION: up & down
Ex. Water waves

8. Anatomy of a Transverse Wave
Rest Position

9. Amplitude & Wave Energy
Amplitude = half of the wave’s height
The larger the amplitude, the more energy the wave carries.

10. Period, Frequency & Wavelength
Wavelength (λ) = the distance between the crests or troughs on a wave
Measured in metric units. (m, cm, km, etc.)
Period (T) = the amount of time it takes for a wave to complete ONE cycle
Measured in seconds
Frequency (f) = the number of waves that pass a point in a certain amount of time, usually ONE second
Measured in Hertz (Hz). 1 Hz = 1 cycle/second
Wave Speed (v) = Wavelength (λ) x Frequency (f)

11. 12/1/15
Ch. 17 Mechanical Waves
Day 2

12. Objectives
SWBAT explain the similarities difference between longitudinal and transverse waves
SWBAT describe what produces each type of wave in nature

13. Wavelength, Frequency, & Energy

14. Longitudinal Waves AKA compressional waves
Matter travels in the same direction as
the wave.
WAVE MOTION: back & forth
Ex. Sound Waves
Transverse vs. Longitudinal Waves

15. Anatomy of a Longitudinal Wave
Compression: particles close together
Rarefaction: particles spread apart
Wavelength: from one compression to the next

16. Transverse & Longitudinal Waves have the same parts
Transverse Wave
Longitudinal Wave
Crest
Compression
Trough
Rarefaction
Amplitude (height above rest)
Amplitude (how tight of compression)
Wavelength (crest to crest or trough to trough)
Wavelength (comp. to comp. or rare. to rare.)
crest
compression
rarefaction
amplitude
wavelength
amplitude
trough
wavelength

17. Think about it
Look at the diagram on the right, and make a hypothesis and a diagram that explains how sound waves are interpreted by our brains? Think about the structure of sound waves, and look at the names of the parts of the ear on the right to give you a clue….

18. Exit Ticket Which wave has the longest wavelength?
Which wave has the highest frequency?
Which wave carries the most energy?
Which wave carries the least energy?
What is the frequency of each series of waves in diagrams A, B, and C?

19. Which wave has the largest amplitude?
Which wave carries the least amount of energy? A B

20. 8. What is the amplitude of the wave? 9. What is the frequency?
(km)