1. Part 1 – Wave Characteristics

2. What is a Wave? A disturbance that carries energy through matter or space.

3. What is a Wave?

4. 2 Categories of Waves Mechanical Waves – Require a medium (material) to travel through – Examples: water waves, sound waves Electromagnetic Waves – Do not require a medium – Example: light travels through empty space

5. Wave Description Crest Trough Amplitude – Intensity of the wave. – How much energy is transferred. Wavelength – The distance from one point on a wave to the same point on the next wave.

6. Wave Description Frequency How frequently a wave pulse occurs. – Unit Hertz (Hz) 1 Hz = 1/seconds or s -1 – Equation

7. Wave Description Period The time (in seconds) that it takes for one wave to pass. – Equation T = Period (in seconds)

8. Wave Description Frequency and Period are Inversely Related

9. Types of Waves Transverse Waves – Matter moves perpendicular to the direction of wave movement.

10. Types of Waves Longitudinal Waves – Matter moves parallel to the direction of wave movement.

11. Other Types of Waves! Surface (water) Waves

12. Wave Interactions – When two (or more) waves are travelling through the same medium they will interact with each other. – The net displacement is the sum of the two waves.

13. Wave Interactions Constructive Interference – The two waves are in-phase. – The Amplitudes add together.

14. Wave Interactions Destructive Interference – Waves are out-of-phase. – Amplitudes “cancel out”

15. Wave Interactions Example: – Shown to the right are four different pairs of wave pulses that move toward and interact with each other. Rank, from most to least, the height of the peak that results when the two pulses coincide. Answer: A,B,D,C

16. Standing Waves A repeated wave produces a pattern caused by the rotation of constructive and destructive interference.

17. Standing Waves

18. Wave Motion Waves transfer energy! Matter has no net movement.

19. Wave Motion Waves transfer energy! Matter has no net movement.

20. Wave Speed Equation Examples 1.A wave with a wavelength of 2 meters has a frequency of 50 Hertz. What is the velocity of the wave? Answer: 100 m/s v = wave velocity (in m/s) f = frequency (in Hertz) λ = wavelength (in meters)

21. Wave Speed Examples 2.Ocean waves are washing up on shore with a velocity of 5 m/s. If they each have a length of 1.5 meters, what is the frequency of the ocean waves? Answer: 3.33 Hz