VIII Light and Optics

Question 1

What is light?

Answer 1

Light is a form of energy that travels in waves.

Question 2

What is energy?

Answer 2

Energy is the ability to cause change.

Question 3

Light appears white yet is ______________________________________.

Answer 3

Light appears white yet is MADE UP OF ALL THE COLORS OF THE RAINBOW.

Question 4

Each color has different ____ and ____.

Answer 4

Each color has different WAVELENGTH** and **STRENGTH.

Question 5

____ has the longest wavelength and lowest energy.

Answer 5

RED has the longest wavelength and lowest energy.

Question 6

____ has the shortest wavelength and highest energy.

Answer 6

VIOLET has the shortest wavelength and highest energy.

Question 7

Light can travel through ____, ____, ____, and ____.

Answer 7

Light can travel through SOLIDS, LIQUIDS, GASSES, and VACUUM.

Question 8

What is a vacuum?

Answer 8

Vacuum is an area with no matter/molecules whatsoever.

Question 9

Light travels much quicker than ____.

Answer 9

Light travels much quicker than SOUND.

Question 10

You ____ lightening before you ____ thunder.

Answer 10

Your SEE** lightening before you **HEAR thunder.

Question 11

Light travels through a vacuum at ____ million meters per second / ____ miles per second. This is believed to be the fastest speed possible in our universe.

Answer 11

Light travels through a vacuum at 300** million meters per second / **186,000 miles per second. This is believed to be the fastest speed possible in our universe.

Question 12

Jet airplanes can fly at several times the speed of ____, but no human-made machine can travel at the speed of ____.

Answer 12

Jet airplanes can fly at several times the speed of SOUND**, but no human-made machine can travel at the speed of **LIGHT.

Question 13

Light travels in ____ ____ or ____ spreading in all directions from a source.

Answer 13

Light travels in STRAIGHT LINES** or **RAYS spreading in all directions from a source.

Question 14

Light cannot ____ or ___ around objects without help.

Answer 14

Light cannot BEND** or **CURVE around objects without help.

Question 15

What are the reasons why shadows outline fingers?

Answer 15

Shadows outline fingers because of Penumbra and Umbra.

Question 16

What is reflected light?

Answer 16

Reflected light is the light that bounces off the surfaces of objects.

Question 17

Most light that reaches your ____ is reflected light.

Answer 17

Most light that reaches your EYE is reflected light.

Question 18

Depending on the ____ of the surface, you may or may not be able to see your own reflection.

Answer 18

Depending on the TEXTURE of the surface, you may or may not be able to see your own reflection.

Question 19

What do smooth surfaces do?

Answer 19

Smooth surfaces reflect images.

Question 20

Give an example of a smooth surface that reflects images?

Answer 20

glass

Question 21

The smooth surface means that light rays all hit the object at the ____ ____ and bounce off at the ____ ____. This creates an image that is reflected back to you.

Answer 21

The smooth surface means that light rays all hit the object at the SAME ANGLE** and bounce off at the **SAME ANGLE. This creates an image that is reflected back to you.

Question 22

What are rough surfaces?

Answer 22

Rough surfaces are surfaces that do not reflect images.

Question 23

Give an example of a rough surface.

Answer 23

walls

Question 24

The rough surface means that all light rays hit the object ____ ____ ____ but then bounce off at ____ ____ ____ ____. The light is mixed, and no reflection can be created.

Answer 24

The rough surface means that all light rays hit the object AT AN ANGLE** but then bounce off at **AT A DIFFERENT ANGLE. The light is mixed, and no reflection can be created.

Question 25

\_\_\_\_ are smooth glass coated with a silvery material that reflects almost all the light that hits it, creating an image.

Answer 25

**_MIRRORS_** are smooth glass coated with a silvery material that reflects almost all the light that hits it, creating an image.

Question 26

Mirrors may be \_\_\_\_, ____ \_\_\_\_, or \_\_\_\_.

Answer 26

Mirrors may be S**_TRAIGHT, CALLED PLANE,**_ or _**CURVED_**.

Question 27

A curved mirror is ____ or \_\_\_\_.

Answer 27

A curved mirror is **_CONCAVE**_ or _**CONVEX_**.

Question 28

What is a plane mirror?

Answer 28

A plane mirror is **_a mirror with a perfectly flat surface_**.

Question 29

A plane mirror reflects an almost \_\_\_\_, ____ \_\_\_\_ \_\_\_\_, and ____ \_\_\_\_ image.

Answer 29

A plane mirror reflects an almost **_IDENTICAL, RIGHT SIDE UP,**_ and _**ACCURATELY SIZED_** image.

Question 30

What is a concave mirror?

Answer 30

A concave mirror **_has a reflective side that bends INward_**.

Question 31

The reflected image of a concave mirror may be ____ \_\_\_\_ \_\_\_\_, ____ \_\_\_\_, bigger or smaller.

Answer 31

The reflected image of a concave mirror may be **_RIGHT SIDE UP, UPSIDE DOWN,_** bigger or smaller.

Question 32

What is a convex mirror?

Answer 32

A convex mirror **_has a reflective side that bends OUTward._**

Question 33

The reflected image of a convex mirror can be bigger or smaller and will ALWAYS be ____ \_\_\_\_ \_\_\_\_.

Answer 33

The reflected image of a convex mirror can be bigger or smaller and will ALWAYS be **_RIGHT SIDE UP_**.

Question 34

Most objects' surfaces do not reflect all light and instead ____ \_\_\_\_ or allow it to ____ \_\_\_\_.

Answer 34

Most objects' surfaces do not reflect all light and instead **_ABSORB IT**_ or allow it to _**PASS THROUGH_**.

Question 35

\_\_\_\_ objects do not allow light waves to pass through.

Answer 35

**_OPAQUE_** objects do not allow light waves to pass through.

Question 36

Examples of opaque objects are ____ , \_\_\_\_, and \_\_\_\_.

Answer 36

Examples of opaque objects are **_WOOD, CARDBOARD**_, and _**METAL._**

Question 37

\_\_\_\_ objects allow light waves to pass through.

Answer 37

**_TRANSPARENT_** objects allow light waves to pass through.

Question 38

Examples of transparent objects are ____ and \_\_\_\_.

Answer 38

Examples of transparent objects are **_GLASS**_ and _**WATER_**.

Question 39

\_\_\_\_ objects transmit light but scatter the rays so that images seen through them look fuzzy.

Answer 39

**_TRANSLUCENT_** objects transmit light but scatter the rays so that images seen through them look fuzzy.

Question 40

Examples of translucent objects are ____ \_\_\_\_ and ____ \_\_\_\_.

Answer 40

Examples of translucent objects are **_WAX PAPER**_ and _**FROSTED GLASS._**

Question 41

Objects do not create or give off their own \_\_\_\_. For example, you can't tell what color a blue book is in a pitch-black room since the book does ____ \_\_\_ ___ \_\_\_\_.

Answer 41

Objects do not create or give off their own **_LIGHT_**. For example, you can't tell what color a blue book is in a pitch-black room since the book does **_NOT EMIT BLUE LIGHT_**.

Question 42

Opaque objects appear to have a certain color since they ____ the same wavelengths of white light and ____ other wavelengths.

Answer 42

Opaque objects appear to have a certain color since they **_ABSORB**_ the same wavelengths of white light and _**REFLECT_** other wavelengths.

Question 43

\_\_\_\_ ____ is made up of all the colors of the rainbow.

Answer 43

**_WHITE LIGHT_** is made up of all the colors of the rainbow.

Question 44

The color you see when you look at an object is ____ \_\_\_\_.

Answer 44

The color you see when you look at an object is **_REFLECTED LIGHT_**.

Question 45

\_\_\_\_ light is *“sucked in”* by an object and does not reach your eyes.

Answer 45

**_ABSORBED_** light is *“sucked in”* by an object and does not reach your eyes.

Question 46

Red shirts appear red because particles in the material ____ red light and ____ all other colors.

Answer 46

Red shirts appear red because particles in the material **_REFLECT**_ red light and _**ABSORB_** all other colors.

Question 47

Black materials absorb ____ light waves and reflect \_\_\_\_.

Answer 47

Black materials absorb **_ALL**_ light waves and reflect _**NONE._**

Question 48

\_\_\_\_ is the absence of light and ___ a true color.

Answer 48

**_BLACK**_ is the absence of light and _**NOT_** a true color.

Question 49

Since black materials absorb light, they tend to be ____ when placed in sunlight.

Answer 49

Since black materials absorb light, they tend to be **_WARMER_** when placed in sunlight.

Question 50

\_\_\_\_ (\_\_\_\_) colored materials reflect all light waves and absorb none.

Answer 50

**_WHITE (LIGHT)_** colored materials reflect all light waves and absorb none.

Question 51

Since white materials reflect light, they tend to stay ____ when placed in sunlight.

Answer 51

Since white materials reflect light, they tend to stay **_COOLER_** when placed in sunlight.