1. Section 2: Wave Properties
Waves, Chapter 11
Section 2: Wave Properties

2. Ways Waves Differ How much energy they carry How fast they travel
How they look
Transverse waves have crests (the highest points) and troughs (the lowest points)

3. Ways Waves Differ How they look
Compressional waves have dense regions called compressions and less dense regions called rarefactions

4. Wavelength & Frequency
Wavelength: the distance between one crest and the next crest
Frequency: how many wavelengths pass a fixed point each second

5. Frequency Expressed in cycles per second, or hertz (Hz)
As frequency increases, wavelength decreases
The frequency of a wave equals the rate of vibration of the source that creates it

6. Wave Velocity
Wave velocity (v) describes how fast the wave moves forward
Velocity = wavelength x frequency, or
v = λ x f
Light waves travel faster than sound waves
lightning vs. thunder: Which comes first?
Sound waves travel faster in liquids and solids than in gases
Light waves travel faster in gases and empty space than in liquids and solids

7. Amplitude Amplitude: a measure of the energy in a wave
The more energy a wave carries, the greater its amplitude

8. Amplitude: Compressional
Amplitude of compressional waves is related to how tightly the medium is pushed together at the compression
The tighter the coils, the more energy it takes to push them together

9. Amplitude: Compressional
The denser the compressions, the larger the amplitude is, and the more energy the wave carries
The less dense the rarefactions, the larger the amplitude is, and the more energy the wave carries

10. Amplitude: Transverse
The distance from the crest or trough of a wave to the rest (normal) position of the medium
Which wave has a greater amplitude (more energy)?