1. Bell Work 3/25 What wave property is determined by the distance between one compression and the next compression of a longitudinal wave? Awavelength Bamplitude Cfrequency Dwave speed

2. Wavelength= distance between any two corresponding locations. Usually measured in one of three ways: 1. crest to next crest 2. trough to next trough 3. from the start of a wave cycle to the next starting point Label the wavelength on both types of waves.

3. Check for Understanding… As a wavelength decreases, the crests of the wave A become wider. B become shorter. C get closer together. D get farther apart.

4. Frequency: The number of waves in given amount of time higher frequency = more energy Units: Hz = Hertz

5. Frequency: Measure the frequency by counting either the number of crests or troughs that pass a point in a certain amount of time.

6. Count the frequency for each wave. High or Low Frequency?

7. Properties of Waves Wave speed is the speed at which a wave travels. Wave speed can be calculated by using the following formula: v = λ x f or v = λ f v = wave speed λ = wavelength f = frequency Determine the wave speed of a wave that has a wavelength of 5 m and a frequency of 4 Hz. Express the units as m/s.

8. Longitudinal vs. Transverse Waves

9. Let’s make waves…

10. Wave Displacement (motion of the particles)

11. Surface Waves

12. Check for Understanding

13. How does the pencil look broken?

14. Wave Interactions The frequencies at which standing waves are made are called resonant frequencies. When an object vibrating at or near the resonant frequency of a second object causes the second object to vibrate, resonance occurs. A resonating object absorbs energy from the vibrating object and vibrates, too. Tacoma Narrows Bridge AKA “Galloping Gertie” is a phenomenon, or an extraordinary event, that caused a lot of destruction because of resonance. Watch this Video!