2. Question of the Day Question: How are topography and bathymetry different? Similar? Answer: ……… Turn In: -Article Summary -Worksheet 14-6

3. Properties of Waves

4. Anatomy of a Wave Wave: a disturbance that carries energy through matter or space Wave: a disturbance that carries energy through matter or space Crest: the highest point of a wave Crest: the highest point of a wave Trough: The lowest point in a wave Trough: The lowest point in a wave

5. Wave Length wavelength: the distance between any two corresponding locations on the wave. wavelength: the distance between any two corresponding locations on the wave. Can be measured from: crest to next crest trough to next trough from the middle of a wave to the middle of the next wave.

6. Amplitude The height of the wave from its center to either a crest or a trough The height of the wave from its center to either a crest or a trough

7. Wave Period the amount of time for one wave to pass by a certain point. the amount of time for one wave to pass by a certain point. Calculate by dividing the amount of time by the number of waves that pass by in that time. Calculate by dividing the amount of time by the number of waves that pass by in that time. A surfer knows that the wave period is important to a good day of surfing. He watches 20 waves go by in 200 seconds. What is the period of the waves? 10 sec/ wave

8. Wave Speed How fast a wave moves How fast a wave moves Remember that Remember that rate= distance / time For a wave For a wave distance= wavelength distance= wavelength Time= wave period Time= wave period Practice: The wavelength of an ocean wave is 10 m and the period of the same wave is 5 seconds. What is the wave speed? 2 m/s

9. Types of Waves Ocean waves Ocean waves Sound waves Sound waves Seismic waves (Earthquake) Seismic waves (Earthquake) Light waves Light waves Electromagnetic spectrum Electromagnetic spectrum

10. Ocean Waves disturbances of water surfaces caused by energy from winds, earthquakes, or volcanic explosions disturbances of water surfaces caused by energy from winds, earthquakes, or volcanic explosions An example of surface waves (waves forming at the boundary between two different materials) An example of surface waves (waves forming at the boundary between two different materials) Most ocean waves at the beach are created by wind Most ocean waves at the beach are created by wind Breakers (above) crash to the beach in Myrtle Beach, South Carolina.

11. What actually happens when a wave goes by? Ocean waves transfer energy rather than actually moving the water along with them. Ocean waves transfer energy rather than actually moving the water along with them. When wave energy passes through water, the water moves in a circular motion. When wave energy passes through water, the water moves in a circular motion. Watch the beach ball in the following animation Watch the beach ball in the following animationanimation The beach ball moves in a circle while the energy of the wave moves from left to right The beach ball moves in a circle while the energy of the wave moves from left to right

12. What actually happens when a wave goes by? The circles that the water particles make get smaller with depth The energy being transmitted decreases with depth Water particles move in a circular pattern down to a depth of ½ the wavelength

13. What happens when a wave reaches the shore? Water deeper than ½ the wavelength Water deeper than ½ the wavelength the energy of the wave moves forward the energy of the wave moves forward the water stays in place. the water stays in place. wave approaches shore wave approaches shore depth of the water is less depth of the water is less than ½ the wavelength the friction against the ocean floor slows the wave down and shortens its wavelength the friction against the ocean floor slows the wave down and shortens its wavelength The wave breaks and crashes on the shore. The wave breaks and crashes on the shore.