1. C H A P T E R 16 Waves and Sound

2. 16.1 The Nature of Waves

3. 16.1 The Nature of Waves Wave is a traveling disturbance.
Wave carries energy from place to place.

4. Types of waves There are two basic types of waves:
Transverse and longitudinal waves.

5. Transverse waves

6. Transverse waves
A transverse wave is one in which the disturbance is perpendicular to the direction of travel of the wave.
Examples: Light wave, waves on a guitar string.

7. Longitudinal Waves

8. Longitudinal Waves
Longitudinal wave is one in which the disturbance is parallel to the line of travel of the wave.
Example: Sound wave in air is a longitudinal wave.

9. Water Waves
Water waves are partly transverse and longitudinal.

10. 16.2 Periodic Waves
Periodic waves are waves that repeat.

11. Amplitude, Wavelength, and Period
The amplitude, A is the maximum disturbance.
The wavelength, λ  is the horizontal length of one cycle of the wave.
The period, T is the time required for one complete up/down cycle of the wave.

12. Frequency
Frequency is the number of waves per unit time.

13. Wave Speed

14. Wave Speed

15. Radio Waves FM vs AM: What's the difference?
AM: The amplitude of the signal is varied to incorporate the sound information. Frequencies are in kHz.
FM: The frequency of the carrier signal is varied to incorporate the sound information. Frequencies are in MHz.

16. FM vs AM Advantages and Disadvantages
FM signals are not affected by static.
With an FM broadcast, slight changes in amplitude don't matter -- since the audio signal is conveyed through changes in frequency, the FM receiver can just ignore changes in amplitude.
AM carrier waves have much longer wavelengths than FM carrier waves, and as a result, they can bend around obstacles like mountains and buildings better than FM waves and can travel greater distances before the signal fades.

17. 16.3. The Speed of a Wave on a String

18. 16.3. The Speed of a Wave on a String