1. Properties of Waves EQ: How do I describe the basic properties of waves and how a wave’s speed is related to its wavelength and frequency?

2. Vocabulary Crest - The highest point, or peak, of a wave. Trough -The lowest point, or valley, of a wave.

3. Properties of Waves There are four wave properties –Amplitude –Wavelength –Frequency –Speed

4. water level at rest fixed point crest trough Frequency is the number of wavelengths passing a fixed point in a certain amount of time, usually 1 second. Wavelength is the distance from one crest or trough to the next. Amplitude is the distance a medium moves above or below its position at rest.

5. Means crest in a transverse wave Means trough in a transverse wave

6. Amplitude The maximum distance that a disturbance causes a medium to move from its rest position; the distance between a crest or trough of a wave and line through the center of a wave. Rope example: move your hand up and down at a greater distance, increases the amplitude. Uses more energy. Slinky – high vibrations cause the compressions to be more crowded and rarefactions loose giving the slinky higher amplitude.

7. Which wave has a greater amplitude?

8. Which longitudinal wave has the larger amplitude? Not very crowded crowded

9. Wavelength The distance between two corresponding parts of a wave

10. Frequency The number of complete waves that pass a given point in a certain amount of time or the number of vibrations per second. Hertz (Hz) – measures frequency. A wave that occurs every second has a measurement of 1 Hz. If two waves pass you every second then the measurement is 2 Hz Example – if you move your hand slower, decreases frequency, move it faster increases frequency.

11. Speed Waves in different mediums travel at different speeds –Ex. Light and sound- see a flash of lighting, hear a clap of thunder –Speed, wavelength and frequency related to each other by the formula Speed = wavelength x frequency F = SW = S W F

12. Go Figure The speed of a wave on a rope is 50 cm/s and its wavelength is 10 cm. What is the frequency? What is the speed of an object that travels 6 meters in 2 seconds? The speed of a wave on a guitar string is 100m/s and the frequency is 1000 Hz. What is the wavelength of the wave?

13. Class Work Homework Fill in –What did I learn –Confused –Say –Read Section 1-2 in your textbook Worksheet