1. What is a wave?
A disturbance that travels through a medium from one location to another location
A medium is a substance or material which carries the wave

2. Rhythmic disturbances that carry energy without carrying matter
What are Waves?
Rhythmic disturbances that carry energy without carrying matter

3. Longitudinal (Compression Waves)
Are composed of
Compressions, where the parts of the medium (coils of the Slinky) are closer together than normal
In this demonstration, you created (generated) compressional longitudinal waves
The waves traveled through a media (the slinky)

4. Vibrates perpendicular (at right angles) to the wave travel
Transverse
Vibrates perpendicular (at right angles) to the wave travel
Electromagnetic waves
Animation courtesy of Dr. Dan Russell, Kettering University

5. A combination of longitudinal & transverse
Water Waves
A combination of longitudinal & transverse
Animation courtesy of Dr. Dan Russell, Kettering University

6. Types of Waves
Mechanical Waves – need matter (or medium) to transfer energy
A medium is the substance through which a wave can travel. Ex. Air; water; particles; strings; solids; liquids; gases
Electromagnetic Waves – DO NOT NEED matter (or medium) to transfer energy
They do not need a medium, but they can go through matter (medium), such as air, water, and glass

7. Electromagnetic Waves
Wave which is capable of transmitting its energy through a vacuum (i.e., empty space)
Produced by the vibration of electrons within atoms on the Sun's surface
Travel through space until they reach Earth
These waves subsequently travel through the vacuum of outer space, subsequently reaching Earth

8. Mechanical Waves
Are not capable of transmitting its energy through a vacuum (space)
Require a medium in order to transport their energy from one location to another

9. Mechanical Waves
Waves traveling through a solid medium can be either transverse waves or longitudinal waves
Waves traveling through a fluid (such as a liquid or a gas) are always longitudinal waves

10. Waves that need matter (medium) to transfer energy:
Mechanical Waves
Waves that need matter (medium) to transfer energy:
Examples: Sound waves, ocean waves, ripples in water, earthquakes, wave of people at a sporting event

11. Some examples of Mechanical Waves

12. Use the next four slides and your Wave Diagram sheet to label and define the parts of a Transverse wave.

13. Parts of a Transverse Wave
The crest is the highest point on a wave.

14. Parts of a Transverse Wave
The trough is the valley between two waves, is the lowest point.

15. Parts of a Transverse Wave
The wavelength is the horizontal distance, either between the crests or troughs of two consecutive waves.

16. Parts of a Transverse Wave
The amplitude is the peak (greatest) value (either positive or negative) of a wave. The distance from the undisturbed level to the trough or crest.

17. An ocean wave is an example of a mechanical transverse wave

19. Compressional Wave (longitudinal)
A mechanical wave in which matter in the medium moves forward and backward along the same direction that the wave travels.
Ex. Sound waves
A slinky is a good illustration of how a compressional wave moves

20. Use the next three slides and your Wave Diagram sheet to label and define the parts of a Compressional wave.

21. Parts of a Compressional Wave (Longitudinal)
The compression is the part of the compressional wave where the particles are crowded together.

22. Parts of a Compressional Wave (Longitudinal)
The rarefaction is the part of the compressional wave where the particles are spread apart.

23. Parts of a Compressional Wave (Longitudinal)
The wavelength is the distance from compression to compression or rarefaction to rarefaction in a compressional wave.

24. Electromagnetic Waves
Waves that DO NOT NEED matter (medium) to transfer energy
Examples: radiation, TV & radio waves, X-rays, microwaves, lasers, energy from the sun, visible light
Electromagnetic waves are considered transverse waves because they have similar characteristics; therefore, they have the same parts.

25. Electromagnetic Spectrum
The electromagnetic spectrum illustrates the range of wavelengths and frequencies of electromagnetic waves.

27. Speed
Frequency (f)- the number of crests of a wave that move past a given point in a given unit of time.
The most common unit of frequency is the hertz (Hz), corresponding to one crest per second. 

28. Speed
Period (T)- Amount of time for a wave to complete one cycle. Measured in seconds (s)

29. Calculating the Speed of a Wave

30. Calculate the Wave Speed
Medium
Wavelength
Frequency
Speed
Zinc,1-in. dia. coils
1.75 m
2.0 Hz
______
0.90 m
3.9 Hz
Copper,1-in. dia. coils
1.19 m
2.1 Hz
0.60 m
4.2 Hz
Zinc,3-in. dia. coils
0.95 m
2.2 Hz
1.82 m
1.2 Hz
3.5 m/s 1. 2.
3.5 m/s 3.
2.5 m/s 4.
2.5 m/s 5.
2.1 m/s 6.
2.2 m/s

31. Reflection
Reflection- When a wave travelling on one medium strikes the surface of a different medium and changes direction so that it returns back into the medium in which it was originally travelling in

32. Reflection Incident Ray- is a ray of light that strikes a surface
Reflected Ray- the ray that represents the light reflected by the surface.
The angle between the surface normal and the reflected ray is known as the angle of reflection.

33. angle of incidence -The angle at which incoming light rays approaches a surface. it is located between the light ray and the normal
angle of reflection- The angle at which light rays are reflected, or bounced off, of a surface

34. Reflection
Law of Reflection- The angle of incidence equals the angle of reflection

35. Reflection with Mirrors
Reflection on plane mirrors- Image in plane mirrors is virtual, upright, laterally inverted at the same distance from the mirror as the object's distance, and the same size as the object

36. Reflection with Mirrors

37. Refraction
Refraction- The change of speed of a wave when the density it travels through, changes. The direction of the wave changes because of the change in speed
Density- The mass of an object
Angle of refraction- The angle between the refracted ray and the normal

39. Critical Angle- A specific value for the angle of incidence that yields an angle of refraction of 90 degrees.
Total internal reflection- the complete reflection that takes place within a substance when the angle of incidence of light striking the surface boundary is greater than the critical angle
Fiber optics- Thin, flexible and transparent fibers that are made of pure glass. They efficiently transmit light pulses over long distances.
Mirages- An optical phenomenon, especially in the desert or at sea, by which the image of some object appears displaced above, below, or to one side of its true position as a result of spatial variations of the index of refraction of air

40. Critical Angle

41. Total Internal Reflection

42. Mirages