Jumpstart & Outro

Objective 11/05/2012 Page 52SWBAT compare light waves and properties to sound waves through notes and video clips.

K W L

K-W-L Chart (What you KNOW, WANT to know and LEARNED about light…….. Go!

Introduction to Light

PAGE 53

1. Why is it that during a thunderstorm, you see the lightning, before you hear the thunder? Or during fireworks you see the colorful explosion, then hear the <<boom>>?

2. If you see lightning strike and you count “1, 2, 3…” seconds, how far away would the storm be?

1. Sound waves travel slower than light waves do! Sound waves travel 330 m/s through the air, while light waves travel 300 million m/s

2. The storm would be 3 miles away

• 3.5- THE STUDENT WILL RECOGNIZE THAT LIGHT IS A FORM OF ENERGY. [P8C1, P8C3]

• Light- a special type of wave that carries energy

• Light is an electromagnetic wave. It does not need a medium in order to travel. – Can travel in a vacuum (as well as

air, water, glass)– Travels through space– Speed: 300 million m/s• Speed of light: written as c• E = mc2

• Light Ray: narrow beam of light that travels in a straight line– Is slowed down and even stopped by

matter (opposite from sound!)

Light vs. SoundSound Light

Type of wave

Travel in Vacuum?

Speed

Speed vs. Medium

Sensation Produced

Variations in Sensations Produced

Wave Diagram

Longitudinal

No, Mechanical wave

~340 m/s (in air)

1,100 feet per second

More elastic/Denser medium = Greater speed of sound

Sound travels through all substances

Hearing

Low frequency = low pitch noteHigh frequency = high pitch note

Transverse

Yes, Electromagnetic wave

300 million m/s (in vacuum)

186,000 miles per second

Light 1/3 slower in water than in air.

Light cannot pass through opaque materials

Seeing

Low frequency = red lightHigh frequency = violet light

“The Magic of Sight—How Our Eyes Work” Video Guide- Page 1 Follow-Up Video Questions

• What purpose do cones play in helping you to see?

• What purpose do rods play?– Why does everything look black & white at night?

• Why do you think cats might see better in the night?– The cat has an increased number of rods. In

humans, 4 out of 5 light-sensitive cells in our retinas are rods, in cats, 25 out of 26 cells are rods.

• Why might dogs see limited colors (just more than black and white)?

It’s a Dog’s Life…

July 11, 1910 - The New York Times

• When light energy is absorbed, it is actually converted into heat energy!

What happens to light rays when they hit an object?- Page 2

• 3.4- THE STUDENT WILL DIFFERENTIATE AMONG REFLECTION, REFRACTION, AND ABSORPTION OF WAVES. [P8C2]• When light rays hit an

object, they are either:– Reflected– Absorbed– Transmitted (pass through

the object)• What you see of an object

depends on how the surface of it reflects light

Types and Behavior of LightDifferent objects allow different amounts of light to pass through themThe amount of light that passes through an object can be described as:Transparent (def.)-You can see objects reflecting on the other side of a transparent object; no blurriness or skewed look.

Ex. Windshield glass, air, saran wrap Translucent (def.)-Light is bent, so you may see the object through the material, but it would be blurry.

Ex. Frosted glass, wax paperOpaque (def.)- You cannot see through them.True / False. Most objects are opaque.

Ex. Wood, metal, wool, cotton

Video

“Translucent, Transparent, Opaque”

Types and Behavior of Light Video Guide- Transparent, Translucent, and Opaque1. When light strikes an object that is transparent it goes right

through.2. Translucent materials will let some of the light through, but

they bend the light so it is hard to see what is on the other side.

3. Most objects are opaque which means they do not allow any light to go through them.

4. The Persistence of vision lets us see the whole image, even though the reflected light comes to us in pieces.

3.8- THE STUDENT WILL EXPLAIN THAT AN OBJECT IS SEEN WHEN light reflected FROM AN object ENTERS THE eye.

Reflection (def.)- The _way that an object appears, is the COLOR of the light that it

reflects.

Jumpstart & Outro

Objective 11/05/2012 Page 52SWBAT compare light waves and properties to sound waves through notes and video clips.

K W L

K-W-L Chart (What you KNOW, WANT to know and LEARNED about light…….. Go!

Jumpstart

Objective 11/08/2012 Page 54

Outro

SW relate and apply the properties of light to the EMS through notes.

Answer the following questions about light using the words: “reflect”, “absorb” or “transmit (pass through)” in your answer.

What do you notice when you wear dark colored clothes outside during the summer?

Why do you think this is? What do you notice when you wear white, or light colored clothes in summer? Why do you think this is?

Title of an article published July 11, 1910 in The New York Times: What is wrong with the

thinking of the people who wrote this article? What do you think they may have meant by this statement? Do dark clothes really keep you cooler?

Light & The EMS

Notebook page 55Packet Page 2

EMS

• HEY!!! Set up your notebook… like this!

Types and Behavior of LightDifferent objects allow different amounts of light to pass through themThe amount of light that passes through an object can be described as:Transparent (def.)-You can see objects reflecting on the other side of a transparent object; no blurriness or skewed look.

Ex. Windshield glass, air, saran wrap Translucent (def.)-Light is bent, so you may see the object through the material, but it would be blurry.

Ex. Frosted glass, wax paperOpaque (def.)- You cannot see through them.True / False. Most objects are opaque.

Ex. Wood, metal, wool, cotton

Video

“Translucent, Transparent, Opaque”

Types and Behavior of Light Video Guide- Transparent, Translucent, and Opaque1. When light strikes an object that is transparent it goes right

through.2. Translucent materials will let some of the light through, but

they bend the light so it is hard to see what is on the other side.

3. Most objects are opaque which means they do not allow any light to go through them.

4. The Persistence of vision lets us see the whole image, even though the reflected light comes to us in pieces.

3.8- THE STUDENT WILL EXPLAIN THAT AN OBJECT IS SEEN WHEN light reflected FROM AN object ENTERS THE eye.

Reflection (def.)- The _way that an object appears, is the COLOR of the light that it

reflects.

EMS

• What is the EMS? • All of the frequencies of electromagnetic radiation– Visible light– X-Rays– Microwaves– Etc…

EMS

• How do we use the EMS?

• Communications• Diagnosing illness• Cooking food• Seeing invisible stuff• Seeing, in general!

What can we draw here to represent “Radio waves”?

Jumpstart

Objective 11/08/2012 Page 54

Outro

SW relate and apply the properties of light to the EMS through notes.

Answer the following questions about light using the words: “reflect”, “absorb” or “transmit (pass through)” in your answer.

What do you notice when you wear dark colored clothes outside during the summer?

Why do you think this is? What do you notice when you wear white, or light colored clothes in summer? Why do you think this is?

Title of an article published July 11, 1910 in The New York Times: What is wrong with the

thinking of the people who wrote this article? What do you think they may have meant by this statement? Do dark clothes really keep you cooler?

Bucket List - Page 31. With your table partners, use your procedure to sort the items

into groups based on properties having to do with reflection, absorption, or transmission of light. Then, discuss with your group why each item is sorted into the pile that it is.

2. In the data table, write the name of the material tested, and the observation of how light interacts with the object (i.e. reflects light, absorbs light, transmits light, does not transmit light, etc.)

3. Based on the diagrams on page 2, try to classify each material based on its properties, and record as your conclusion (transparent, translucent, opaque).

4. Draw conclusions based on your data. Classify based on the best transmitter of light, and the worst transmitter of light.

Material Tested Observation Conclusion

Opaque, Transparent, Translucent Lab- Page 3• Different objects allow different amounts of light to pass

through them• The amount of light that passes through an object can be

described as:– Transparent– Translucent– Opaque

• Now, using the diagrams provided, write a hypothesis (IF, THEN, BECAUSE) for transparent, translucent, and opaque items.

Opaque, Transparent, Translucent Lab- Designing the Experiment- Page 3

• Materials in your bucket: (you may need to add some lines to your materials section of the lab)– Balloon– Black paper– Cardboard– Plastic sandwich bag– Wax paper– Metal soup can– Graduated cylinder– Yellow plastic wrapping

paper

– White tissue paper– Blue felt fabric– Cling (Saran) wrap– Protractor– Plastic cup (2 kinds)– Plastic grocery bag– Plastic colored square w/ handle

– Mirror– Straw– Lab apron– Optional: Choose two of

your own objects to use!

Procedure- Page 3• Are there things you do every night before

you go to bed? Are there things you do every morning when you wake up?

• What is your “procedure” for what you do before you go to bed, and in the morning?

1. Brush teeth2. Wash face3. Make Lunch4. Set alarm Clock…5. Etc.

– How do you dry off after a shower?!

• You must write a procedure for how you are going to test and classify each item as either transparent, translucent or opaque.