2. Wave Definition: A disturbance that transfers energy from place to place. A medium, a medium is the material through which a wave travels. A medium can be a gas, liquid, or solid.

3. What causes waves? Waves are created when a source of energy causes a medium to vibrate. A vibration is a repeated back and forth or up and down motion.

4. Mechanical Waves Mechanical Waves (sound) require a medium to travel Waves are classified according to how they move.

5. Transverse wave Waves that move the medium at right angles to the direction in which the waves are traveling is called a transverse wave. The highest parts are called crests the lowest parts are called troughs.

6. Compressional Wave Matter vibrates in the same direction as the wave travels. Example: Slinky

7. Compressional wave The parts,where the coils are close together are called compressions, the parts where the coils are spread out are called rarefactions.

8. Electromagnetic Waves EM Waves (light) do not require a medium to travel

9. Properties of Waves

10. Basic Properties of Waves Amplitude Wavelength Frequency Speed

11. Amplitude Amplitude is the maximum distance the particles of the medium carrying the wave move away from their rest positions.

12. Wavelength The distance a wave travels before it repeats is called the wavelength. Transverse measure from crest to crest or trough to trough. Longitudinal measure from one compression to the next.

13. Frequency The number of complete waves that pass a given point in a certain amount of time. Number of vibrations per second. Frequency measured in hertz (Hz).

14. Speed Waves Waves in different mediums travel at different speeds. Solids (Steel)= fastest Liquid (Water) = middle Gas (Air) = slowest

16. Ways Waves Interact Reflection Refraction Diffraction Interference Constructive Destructive

17. Reflection When an object or wave hits a surface through which it cannot pass, it bounces back. Examples Mirror (light) Echo (sound)

18. - Refraction is when a wave moves from one medium into another medium - Wave changes speed as it enters the second medium which causes it to bend

19. Diffraction When a wave passes a barrier or moves through a hole in a barrier it bends and spreads out.

20. Interference Constructive interference occurs whenever two waves combine to make a wave with a larger amplitude. Destructive interference when the amplitudes of two waves combine producing a smaller amplitude.

21. Constructive Interference Destructive Interference