Unit 2, Lesson 2 Light

Front 1

prism

Back 1

A thick piece of glass that bends light separating white light into bands of colored light.

Front 2

electromagnetic spectrum

Back 2

A range of all light waves of varying wavelengths including the visible spectrum

Front 3

refraction

Back 3

The bending of light as it passes from one material into another

Front 4

reflection

Back 4

Bouncing of lightwaves off a surface

Front 5

transparent

Back 5

letting all light through so objects on the other side can be seen clearly

Front 6

translucent

Back 6

letting only some light through so objects on the other side appear blurry.

Front 7

opaque

Back 7

completely blocking light from passing through.

Front 8

What is light?

Back 8

Light is the form of energy we detect with our eyes.

Front 9

Where does light come from?

Back 9

It comes from the Sun, fireflies, lightbulbs, fire, and other sources.

Front 10

Who was the first person to show that white light is made of all the colors we can see?

Back 10

Newton

Front 11

What colors make up the visible spectrum that Newton talked about?

Back 11

ROYGBIV

Front 12

Like sound, light travels in ____________

Back 12

waves

Front 13

Light waves in the electromagnetic spectrum have _______________?

Back 13

different wavelengths

Front 14

Light waves carry a different amount of ______________?

Back 14

energy

Front 15

The longer the wavelength,...

Back 15

the less energy it has.

Front 16

What waves have the longest wavelengths?

Back 16

Radio waves

Front 17

What waves have the shortest wavelength with the most energy?

Back 17

Gamma waves

Front 18

How can light waves be helpful?

Back 18

Helpful: microwave oven uses light waves to heat up food.

Front 19

How can light waves be harmful?

Back 19

Harmful: (UV) Ultraviolet rays are dangerous and can burn your skin.

Front 20

List the directions light waves can spread out.

Back 20

Straight lines or rays

Front 21

What can light rays travel through?

Back 21

air, water, and space.

Front 22

What happens when light rays pass from glass to water?

Back 22

The light rays bend.

Front 23

What happens when light moves from cold air into warm air?

Back 23

Refraction

Front 24

Unlike sound, light travels more slowly through what kind of material?

Back 24

Denser material

Front 25

What happens to light at the point when it hits denser material?

Back 25

It slows and bends.

Ex: water is denser than air, so light rays refract where water and air meet.

Front 26

A lens is a tool that does what?

Back 26

A lens bends light.s

Front 27

A concave lens curves

Back 27

inward.

Front 28

Light in a lens bends __________ from the center of the lens.

Back 28

Outward

Ex. Glasses that help you see at a distance have a concave lens.

Front 29

A convex lens bulges __________.

Back 29

Outward

Light rays bends inward toward its center

Ex. Reading glasses have a convex lens.

Front 30

What happens when light bounces off objects?

Back 30

It enters the eye.

Front 31

List the steps on how light bounces off objects and enters the eye

Back 31

1. light passes through an opening in the eye called the pupil

2. from the pupil, light moves through the lens at the front of the eye. The image is focused on the retina. The retina is in the back of the eye.

3. the image that the lens focuses onto the retina is upside down. The retina changes the image into signals.

4. The optic nerve brings the signals to the brain.

The brain interprets the images right side up.

Front 32

Most of the light that reaches your eyes is

Back 32

reflected light

Front 33

What kind of surfaces reflects almost all the light that falls on it.

Back 33

Smooth shiny surfaces such as mirrors

Front 34

What type of surfaces reflect the least amount of light?

Back 34

Dull, rough surfaces

Front 35

The color of an object depends on

Back 35

the colors it reflects. Ex: a green leaf reflects only the green wavelengths of the visible spectrum. It absorbs, or takes in, all the other colors.

Front 36

What is the Law of Reflection?

Back 36

When light reflects off a surface, it changes direction.

Front 37

Based on the Law of Reflections, light rays moving toward a surface are called

Back 37

incoming rays

Front 38

Based on the Law of Reflections, reflected light rays are called

Back 38

outgoing rays

Front 39

Incoming rays strike a surface at an angle called the

Back 39

incoming angle

Front 40

Outgoing rays reflect an angle called the

Back 40

outgoing angle

Front 41

Incoming & outgoing angle are always

Back 41

equal. The relationship b/w the angles is called law of reflection

Front 42

Some materials are transparent. They allow light to pass

Back 42

through them.

Front 43

Light travels in a

Back 43

straight line

Front 44

Opaque materials

Back 44

block light completely.