1. WavesSection 2 Bellringer In the diagram, A is the distance from a point on one wave to an identical point on the next wave. What might this distance be called? 1.In the diagram, B is the amplitude of a wave. What do you think this is a measure of? 2.Twenty waves pass by a point in a certain amount of time. Would this be a measure of a wave’s speed or frequency?

2. WavesSection 2 Wave Properties What are some ways to measure and compare waves?

3. WavesSection 2 15-2-1 Wave Properties, continued amplitude: the maximum distance in meters that the particles of a wave’s medium vibrate from their rest position

4. WavesSection 2 15-2-2 Wave Properties, continued for a transverse wave, measured from the rest position to the crest or the trough

5. WavesSection 2 15-2-3 Wave Properties, continued Wavelength (  : the distance in meters from any point on a wave to an identical point on the next wave

6. WavesSection 2 15-2-4 Wave Properties, continued The greater the amplitude, the greater the energy in a wave.

7. WavesSection 2 15-2-5 Wave Properties, continued The greater the wavelength, the less the energy in a wave.

8. WavesSection 2 15-2-6 Wave Properties, continued period (T ): in physics, the time in seconds that it takes a complete cycle or wave oscillation to occur

9. WavesSection 2 15-2-7 Wave Properties, continued –Frequency (f): the number of cycles or vibrations per unit of time expressed in hertz (Hz); also the number of waves produced in a given amount of time

10. WavesSection 2 Wave Speed How can you calculate the speed of a wave?

11. WavesSection 2 15-2-9 Wave Speed The speed of a wave is equal to wavelength divided by period, or frequency multiplied by wavelength.

12. WavesSection 2 15-2-13 Wave Speed, continued In general, wave speed is greatest in solids and least in gases.

13. WavesSection 2 15-2-14 Wave Speed, continued In a given medium, the speed of waves is constant.

14. WavesSection 2 15-2-15 Wave Speed, continued the speed of light (c) in a vaccum = 3.00  10 8 m/s c = f 

15. WavesSection 2 The Doppler Effect Why does the pitch of an ambulance siren change as the ambulance rushes past you?

16. WavesSection 2 15-2-16 The Doppler Effect, continued Doppler effect: an observed change in the frequency of any type of wave when the source or observer is moving

17. WavesSection 2 15-2-17 The Doppler Effect, continued The frequency of sound waves from a source moving toward an observer is higher than if the observer was moving with the source and lower when the source is moving away.