1. What is light?

2. Light Make a list of things that give us light. How many can you think of?

3. Light Light is form of _______ that you can _____. Light is on kind of _____________. Light comes from ______ different _______. Some items _______ light while others ______ light. energy see radiant energy many sources produce reflect

4. Light Is it a producer or a reflector? – Candleproducerreflector – Mirrorproducerreflector – Sunproducerreflector – Flashlightproducerreflector – Jupiterproducerreflector

5. Light Name four other objects that produce light. fire stars lantern Light bulb lamp laser candles lightning The sun Fireflies Flashlights

6. Light Name four other objects that reflect light. The moon Metal Glass Water Mirrors Snow Flashlights

7. Think About It Where do you sit when you watch television? You sit in front of the television to watch it.

8. Laser Pointer Turn off the classroom lights. Carefully point a laser pointer at a wall. Clap chalk erasers together ( or shake a nylon bag of flour) between the wall and the laser pointer. Record your observations:________________ _____________________________________

9. How Does Light Travel? Light ______ in a __________. Can you think of some real-life examples of light traveling in a straight line? travels straight line Television Flashlight Laser Lamp

10. Light Experiments Each light source will be observed for five characteristics 1.Color of the light 2.Intensity (Brightness) 3.Heat produced 4.How the light travels 5.Real life uses

11. Light Experiments 1.Color of the light – Turn on the light. – What color is it? – Record this information

12. Light Experiments 2. Intensity (Brightness) – Turn on the light. – How bright is it? – Can look at it directly without hurting your eyes? (Use caution!) – Rank the intensity on a scale of 1-5 with 1 being very weak and 5 being too bright to look at. – Record this information

13. Light Experiments 3. Heat produced – Turn on the light – Place your hand in front of the beam. – How much heat do you feel? How long can you leave your hand there? (Use caution!) – Rank the heat on a scale of 1-5 with 1 being very weak or cool and 5 being very hot. – Record this information

14. Light Experiments 4. How the light Travels – Turn on the light. – We know light travels in a straight line. – How do the individual light beams travel from this light source? Are they all forced in one direction, or are they able to travel in many directions? – Illustrate low the light travels from its source

15. Light Experiments 5. Real life uses – What would you use this light for in real life? – Think about its properties. What uses does it have? When have you used a similar light? Why? – Examples: – Record at least one use per light source Light an entire room Look down a tiny hole Find shoes in a dark closet Highlight a word on a screen Point to a star during a show Light the Earth Find a missing ball at night Tell stories in the dark Holiday decorations Carry with you in a backpack Signal to a friend across the street

16. Light Experiments Light Source Color of the Light Intensity or Brightness Heat Produced Illustrate how it Travels Real Life Uses 1 2 3 4 5

17. Light Experiments Light Source Color of the Light Intensity or Brightness Heat Produced Illustrate how it Travels Real Life Uses 1 2 3 4 5

18. Reflection Light can be ________ or ________ by a surface. When light is ________, it __________ that surface. – Example: ________ When light is _________, it is _______ by that surface. – Example: __________ Light is _________ off a surface in a special way. reflected absorbed reflected Bounces off mirror absorbed trapped Your body reflected

19. Partner Activity: Bouncing Tennis Balls Illustrate what you observed while rolling, bouncing, and catching the tennis ball.

20. Demonstration: Basketball Illustrate what you observed while bouncing and catching the basketball.

21. Light Reflection The __________ and the _________ actually represent what happens to ____ as it is ________. When ____ hits a _________ surface, like a ______, it will ___________ at the __________. The angle at which light ______________ is the _______________. tennis ball basketball light reflected lightreflective mirrorbounce back Same angle strikes a surface angle of incidence

22. Light Reflection The angle at which light __________ a surface is the ________________. The angle of incidence is   = to the angle of reflection. Example: When _____ strikes a ______ at a ____ angle, it is reflected at a ____ angle. Draw and label an illustration of this property of light. reflects off angle of reflection lightmirror 45 

23. Reflection Activities Review about light and reflection – Light travels in a straight line – Angle of Incidence – Angle of Reflection – Angle of Incidence = Angle of Reflection

24. Reflection Activities Group Reflection Challenge Can you move light? Can you use what you know about the angle of incidence and the angle of reflection to move light? Let’s find out!

25. Reflection Activities Set up: Stand the textbook up on the desk. Lay the flashlight on a desk facing one cover of the textbook. Turn on the flashlight, so you can see the light on the cover.

26. Reflection Activities The Challenge: Move the light from one side of the text book to the other, but the rules are: you cannot move the flashlight or the textbook. You may only use the mirrors and what you know about light. When you have successfully found the solution, illustrate and label your solution.

27. Reflection Activities Class Reflection Challenge: – Have we really mastered how light moves? Let’s find out! – Give each student a mirror. The teacher will carefully point a laser pointer into one mirror. Let’s see if we can get the light to reflect in every other mirror in the classroom.

28. Reflection Activities What worked well? What didn’t? Why?

29. Reflection Activities What would you do differently? What is our record for the most number of mirrors reflected?

30. Mirrors that Multiply Test angle AOJ. How many faces do you see? Test angle BOI. How many faces do you see? Test angle COH. How many faces do you see? Test angle DOG. How many faces do you see? Test angle EOF. How many faces do you see?

31. Mirrors that Multiply What pattern do you see? The larger the angle, the _____ faces. The smaller the angle, the _____ faces. Why? fewer more As the angle gets smaller, the light is able to reflect back and forth in the mirror more frequently resulting in more images.

32. Butterfly Design We can use mirrors to create designs. We can also place mirrors on existing patterns to create new designs. Using a single mirror to reflect portions of the butterfly picture, you will create a new design.

33. Reflection Experiments We know light reflects off a mirror. We’ve done many challenges and activities using mirrors to reflect light. Is a mirror the only thing that can reflect light? Today we’ll experiment with different surfaces to see if they will reflect light. No

34. Sandpaper Wax Paper Small White Board Smooth Foil Crumpled Foil White Paper Canning Jar Lid Colored Cellophane Black Paper Jelly Jar Saran Wrap Reflection Experiments

35. Turn off the classroom lights. Test each item by placing it on a desk and shining a flashlight on the surface. Reflect the light onto a plain piece of white paper. Record your observations about the reflection including size and intensity.

36. Reflected, Absorbed, or Transmitted? Light that _____________ matter is __________ by the material. If light is not __________, some of it is ________. If light is not __________ or ________, it is ________. passes through transmitted reflected transmitted reflected absorbed

37. Reflected, Absorbed, or Transmitted? There are three types of materials: 1.Transparent: 2.Translucent: 3.Opaque: light is transmitted (passes through) some light is transmitted, some is reflected and scattered light is absorbed (not transmitted)

38. Transparent, Translucent, or Opaque? TransparentTranslucentOpaque

39. Refraction Activity: Cup of Water Put your thumb in the glass of water. What do you observe? Put a drinking straw or pen/pencil in the glass of water. What do you observe? Thumb in the Cup of WaterStraw in the Cup of Water Illustrate

40. Refraction When an object is placed in a glass of _____ it appears to be ________________________. This is because of light ________. Light changes ________ when it enters a new ________. A medium is any _________ through which a _____ is __________. Example: ____ is traveling from the overhead light bulbs through ___. When the _______ enters the cup of _____, it enters a new ________. This causes the _____ to change _________. water broken or shifted to the side refraction direction medium substance wave transmitted Light air light water medium lightdirection

41. Refraction Light in ___ travels ____. Light in _____ travels ___________. When light ___________, it changes ________. When light changes ________ or _____, it is called _________. _________is caused by the change of the ____________ as it travels through different ________. airfast water more slowly slows down direction bends refraction Refraction speed of light mediums

42. Activity: Throwing Contest Who has a great throwing arm? Who won? Why? laser

43. Speed of Light The speed of light is _____________________ That is the same as _____________________ ______________. This is how fast light travels in ___. When it enters a new ________ (like water), it slows down. The result is _________. 186,000 miles per second 7.5 times around the Earth in 1 second air medium refraction

44. Speed of Light Look at the cup from the side so you can still see the bottom of the inside of the cup, but you cannot see the coin glued to the bottom. Slowly pour water into the cup until you see the coin appear. Why does it work? Refraction

45. Refraction Experiments Variable: Amount of Water First, let’s experiment by changing the amount of water and see how it affects refraction. We will measure 50 mL, 100 mL, 150 mL, and 200 mL of water into four different clear plastic cups. Place a drinking straw in each cup being sure the angle of the straw is the same for each container. Record your observations.

46. Refraction Experiments 50 mL of Water100 mL of Water150 mL of Water200 mL of Water Illustrate Observation

47. Refraction Experiments Variable: Type of Liquid Now let’s experiment by changing the type of liquid and see how it affects refraction. We will measure 100 mL of water, vegetable oil, karo syrup, and rubbing alcohol into four different clear plastic cups. Place a drinking straw in each cup being sure the angle of the straw is the same for each container. Record your observations

48. Refraction Experiments 100 mL of Water100 mL of Vegetable Oil 100 mL of Karo Syrup 100 mL of Rubbing Alcohol Illustrate Observation

49. Color of Light Light _______ in ______.travelswaves

50. Color of Light __________ is the measure of the number of ______ that pass by a given point in one second. Remember, ______ is one kind of _______energy. Radiant energy includes ______ of all different ___________ and ___________. When all the types of _____________ are arranged in ______, we have the _______________________. Frequency waves lightradiant waves wavelengthsfrequencies Radiant energy order Electromagnetic Spectrum

51. Color of Light

52. Radio: Yes, this is the same kind of energy that radio stations emit into the air for your stereo to capture and turn into your favorite tunes. But radio waves are also emitted by other things…such as stars and gases in space. You may not be able to dance to what these objects emit, but you can use it to learn what they are made of.

53. Color of Light Microwaves: They will cook your popcorn in just a few minutes! Microwaves in space are used by astronomers to learn about the structure of nearby galaxies, and our own Milky Way!

54. Color of Light Infrared: We often think of this as being the same thing as ‘heat’, because it makes our skin feel warm. In space, IR light maps the dust between stars.

55. Color of Light Visible: Yes, this is the part that our eyes see. Visible radiation is emitted by everything from fireflies to light bulbs to stars…also by fast- moving particles hitting other particles.

56. Color of Light Ultraviolet: We know that the Sun is a source of ultraviolet (or UV) radiation, because it is the UV rays that cause our skin to burn! Stars and other “hot” objects in space emit UV radiation.

57. Color of Light X-rays: Your doctor uses them to look at your bones and your dentist to look at your teeth. Hot gases in the Universe also emit X-rays.

58. Color of Light Gamma-rays: Radioactive materials (some natural and others made by man in things like nuclear power plants) can emit gamma-rays. Big particle accelerators that scientists use to help them understand what matter is made of can sometimes generate gamma- rays. But the biggest gamma-ray generator of all is the Universe! It makes gamma radiation in all kinds of ways.

59. Color of Light http://imagine.gsfc.nasa.gov/docs/science/kno w_l1/emspectrum.html

60. Visible light We can only see one portion of the electromagnetic spectrum. That portion is called __________. What color is the light from most light bulbs? Although we see _____ light, it is actually made up of many ______. The colors of the spectrum are: ____________ ______________________ An easy way to remember these colors in order is __________ visible light white colors red, orange, yellow, green, blue, violet ROY G. BiV

61. Class Activity: Prism Glasses White light appears while to our eyes, but it is actually made up of the colors of the visible light spectrum. Let’s use glasses with special lenses to help us see these colors. Record your observations.

62. Class Activity: Prisms Prisms separate light into the colors of the spectrum. Use a prism and a flashlight to see if you can create a rainbow. What technique works best? Is a prism the only way we see a rainbow? When do you usually see a natural rainbow? How was the rainbow created? What caused the sunlight to separate? No After rain The water vapor left in the air after a rain storm acts as a prism to separate the light.

63. Activity: Blending Light We can use a prism to separate the colors of white light, so we can see all the colors of the spectrum. Is it possible to blend the colors of light and make white? Let’s find out. The primary colors of pigment (paint) are red, yellow, and blue. We can mix these colors to make secondary or tertiary colors. If you mix all the primary colors, you get “yuck.”

64. Activity: Blending Light The primary colors of light are red, green, and blue. What happens if we mix them together? Record your observations.

65. Colors If light is made of all the colors of the spectrum, how do we see certain colors? Why do we see white, black, or red? Illustrate and explain.

66. Colors Why we see white: All the colors of the spectrum strike the surface. All the colors of the spectrum are reflected to our eyes.

67. Colors Why we see black: All the colors of the spectrum strike the surface. All the colors of the spectrum are absorbed. (None are reflected)

68. Colors Why we see red: All the colors of the spectrum strike the surface. Red is reflected to our eyes. The rest of the colors are absorbed.

69. Colors Now try two on your own… Why we see yellow: Why we see green: All the colors of the spectrum strike the surface. Yellow is reflected to our eyes. The rest of the colors are absorbed. All the colors of the spectrum strike the surface. Green is reflected to our eyes. The rest of the colors are absorbed.

70. Summary Light can be ________ (__________) Light can be ________ (______) Light can be ________ (____) Light can be _________ (_____________) reflectedbounced off absorbedtrapped refracted bent separated creates rainbow

71. Color of Light Experiment Test each object according to the chart. Record the color observed. Object Color: Red Filter Orange Filter Yellow Filter Green Filter Blue Filter Violet Filter Red Orange Yellow

72. Color of Light Experiment Object Color: Red Filter Orange Filter Yellow Filter Green Filter Blue Filter Violet Filter Green Blue Violet White

73. Color of Light Experiment Layer the colored filters and see what effect are created. Record your results.