1. Waves G10 Team International School of Guangzhou

2. Waves: The Basic Types What is a wave??? A form of energy produced and transmitted by vibrating matter Carry energy from place to place, but the medium (particles/matter) the waves travel through do NOT go along for the ride EX: Sound wave ENERGY travels through the air in the form of vibrations, but air particles don’t travel along with the wave ENERGY

3. Tokyo Wave Pool

4. How waves move: Vibration: describes the back and forth movement of particles Propagation: is the direction that ENERGY/waves travel

5. Propagation of Electromagnetic Waves

6. Types of Waves Transverse Waves Longitudinal Waves Electromagnetic Waves

7. Transverse Waves

8. Examples: Examples of Transverse Waves Include: Water Seismic Waves

9. Longitudinal Waves:

10. Examples of Longitudinal Waves Examples of Longitudinal waves include: Sound

11. Electromagnetic Waves

12. Electromagnetic Waves Continued Electromagnetic Waves consist of TWO transverse waves that are perpendicular Examples: Visible light Radio Waves X-rays

13. Definitions you NEED to know: Wavelength: the distance between one part of a wave and the same point on the next wave (symbol is λ). Crest: The top of the wave Trough: The bottom of the wave Amplitude: distance from undisturbed position (the straight line on the picture between the crests and troughs) to the top of the crest OR the bottom of the trough.

14. Frequency The FREQUENCY of a wave refers to the number of waves that pass a given point per unit time (per second) Metric Unit = Hertz (Hz) 1 vibration/second= 1 Hz 10 vibrations/second= 10 Hz Higher Frequencies kHz (kilohertz) MHz (Megahertz) AM radio waves are usually in kHz (EX.) 96.5 kHz would broadcast radio waves @ a frequency of 96,500 Hz

15. Wave Period A PERIOD refers to the time (seconds) it takes for one complete oscillation Frequency (f) and period (T) are inversely related f = 1/T If the string on a harp makes five vibrations in one second then the frequency is: ___________ How long does it take for just one vibration (period)?

16. Frequency and Periods are Inversely Related f = 1 / T T = 1 / f A hummingbird’s wings complete 25 back and forth vibrations every second. What is the frequency? Period? Gusts of wind cause the new TV tower in Guangzhou to sway back and forth, completing a cycle every 10 seconds. What is the frequency? Period?