1. Chapter 1 – Waves
1.1 What are Waves?

2. I. Essential Question: What Forms Mechanical Waves?
What Are the Types of Mechanical Waves?

3. II. Key Vocabulary
Wave: a disturbance involving the transfer of energy from place to place.
Energy: the ability to do work
Medium: the material through which a wave travels
Mechanical waves: waves that require a medium
Vibration: repeated back and forth or up and down motion.

4. II. Key Vocabulary
Transverse wave: a wave that vibrates the medium at right angles (perpendicular) to the direction in which the wave travels.
Crest: the high point on a transverse wave
Trough: the low point on a transverse wave
Longitudinal wave: a wave that vibrates the medium in the same direction in which the wave travels.

5. II. Key Vocabulary
Compression: an area in a long. wave in which the coils are close together.
Rarefaction: an area in a long. wave in which the coils are spread out.
Surface waves: a combination of transverse and longitudinal waves.

6. III. Key Concepts Gases, liquids, and solids can all be mediums.
Mechanical waves form when a source of energy causes a medium to vibrate.
The waves made from a moving a rope up and down are transverse waves; a spring is an example of a longitudinal wave.

7. III. Key Concepts
Parts of a transverse wave:

8. III. Key Concepts
Parts of a longitudinal wave:

9. III. Key Concepts
Surface waves travel along a surface that separates two mediums.
Example: ocean waves travel between water and air

10. Chapter 1 – Waves
1.2 Properties of Waves

11. I. Essential Question:
What are the amplitude, wavelength, frequency, and speed of a wave?
How are frequency, wavelength, and speed related?

12. II. Key Vocabulary
Amplitude: the maximum distance the medium vibrates from the rest position.
Wavelength: the distance between two corresponding parts of a wave.
Frequency: the number of waves that pass a given point in a certain amount of time.
Hertz: the unit used to measure frequency (number of waves per second)
Speed: how far the wave travels in a given amount of time.

13. III. Key Concepts

14. III. Key Concepts Amplitude: Height of a wave’s crest depends on it
High waves have more energy and more amplitude
In transverse waves, it’s the highpoint or low point of the wave; in long. waves it’s how densely compacted the waves are.

15. III. Key Concepts
Amplitude:

16. III. Key Concepts Wavelength:
Transverse waves: distance from crest to crest or trough to trough
Longitudinal waves: distance between compressions
The closer the waves are together, the higher the frequency.

17. III. Key Concepts
Wavelength:

18. III. Key Concepts Speed:
Light waves travel much faster than sound waves
Determined by dividing the distance a wave travels by the time it takes to travel that distance. (speed = distance / time)
Temperature, pressure, and type of medium may change the speed that waves travel.

19. III. Key Concepts Speed = (wavelength)(frequency)
Frequency = speed / wavelength
Wavelength = speed / frequency

20. Chapter 1 – Waves
1.3 Interactions of Waves

21. I. Essential Question: What changes the direction of a wave?
What are the two types of wave interference?
How do standing waves form?

22. II. Key Vocabulary
Reflection: the bouncing of a wave off of a surface that it cannot pass through.
Refraction: the bending of waves due to a change in speed.
Diffraction: the bending of a wave or passing through an opening of a barrier.
Interference: the interaction between waves that meet

23. II. Key Vocabulary
Constructive interference: when waves combine to form a wave with a larger amplitude
Destructive interference: when waves combine to form a wave with a smaller amplitude
Standing wave: a wave that appear to stand in one place, but is really two waves interfering as they pass.

24. II. Key Vocabulary
Node: points of zero amplitude formed by destructive interference; evenly spaced.
Antinode: points of maximum amplitude of a standing wave; halfway between two nodes.
Resonance: an increase in the amplitude of a wave vibration that occurs when external vibrations match an object’s natural frequency.

25. III. Key Concepts

26. III. Key Concepts
Reflection:

27. III. Key Concepts Refraction:
When a wave enters a new medium, one half enters before the other half, causing a bend.
This does not occur if waves enter the new medium at a right angle.

28. III. Key Concepts
Diffraction:

29. III. Key Concepts Constructive Interference:
Waves add their energies together by overlapping their crests/troughs.

30. III. Key Concepts Standing wave:
When a wave and a reflected wave meet one another.

31. III. Key Concepts Resonance:
Most object’s have a natural frequency of vibration. If this is met, it causes even greater oscillations/waves.