1. Light
PS 9

3. Light Waves Electromagnetic waves
Combination of electric and magnetic fields
Do not require a medium to travel through
Electromagnetic waves are transverse waves
Travel at 300,000,000 m/s (3 x 108 m/s)

4. Light can… pass through anything that is transparent
pass partially through anything that is translucent
not pass through things that are opaque.

6. Light Waves Wavelength Frequency
Measures the distance from crest to crest or trough to trough
Wavelength determines the color of the light
Frequency
Measures the amount of waves that pass a point per second (Hz)

7. Light Waves Amplitude Speed
Measures the distance from the rest position to a crest or trough
Amplitude is the brightness of the light
Speed
How far a wave travels in one unit of time

8. Light Waves Formulas Speed = wavelength x frequency
Frequency = speed ÷ wavelength
Wavelength = speed ÷ frequency
As wavelength increases, frequency decreases
As frequency increases, wavelength decreases

9. Reflection Reflection
A wave hits a surface through which it cannot pass; it bounces back
Usually happens on
opaque objects, but
can also happen on
translucent and
transparent objects

11. Specular Reflection
Reflection on a smooth surface

12. Diffused Reflection
Reflection on an uneven surface

13. Reflection
Plane Mirror: flat mirror that forms an image that is always right side up, same size as the real object, and same distance away from the mirror as the real object

14. Reflection
Concave mirror: mirror that curves inward that forms images depending on the object’s position from the mirror.
Ex: make-up mirror, flashlights, car headlights, telescopes

15. Concave Mirror Object farther away = image upside down and smaller
Object medium distance away = image upside down and larger
Object close = image right side up and larger

17. Reflection
Convex mirror: mirror that curves outward and forms images that are always right side up and appear smaller and farther away than they really are.

18. Convex Mirror Examples

20. Refraction Refraction The bending of waves due to change in speed
If white light is bent it turns into the visible spectrum
If the visible spectrum is bent it turns back to white light

22. Refraction
Concave lens a lens that curves inward and creates an image that spreads light to produce an image that is right side up

23. Concave Lens

24. Refraction
Convex lens: a lens that curves outward, directing light to a center focal point

25. Refraction Object farther away = images upside down and smaller
Object medium distance away = image upside down and larger
Object close up = image upright and large

26. Viewed through a Convex lens at a medium distance
Seed Pod
Before
Seed Pod
Viewed through a Convex lens at a medium distance
Convex Lens
Used close up

27. Diffraction
The bending of waves around the edge of a barrier

28. Interference
Two waves meet
Constructive
Destructive