Light Target Sheet

Question 1

How light travels?

Answer 1

Light travels through waves

Question 2

Know that light travels from a source

Answer 2

Luminous objects/Sun

Question 3

How shadows are formed?

Answer 3

An object must block light, and they are translucent or opaque

Question 4

What is the speed of light?

Answer 4

It travels at 300,000km/s

Question 5

What materials light can travel through?

Answer 5

Translucent and transparent materials

Question 6

Which materials absorb the most light?

Answer 6

The dark and dull colors

Question 7

How do we see things?

Answer 7

Light from an object enters directly into our eyes
You see some objects because they are light sources
You see other objects by reflected light

Question 8

What happens when light hits an object?

Answer 8

Can be transmitted, reflected or absorbed by an objects

Question 9

What happens when light reflects off different objects?

Answer 9

It goes directly on to your eye

Question 10

What is a plane mirror?

Answer 10

A plane mirror reflects light regularly so that produces a clear image.

Question 11

Relationship between the object and the image in a plane mirror

Answer 11

That are the same size

Question 12

What is the relationship between the incident ray and the reflected ray?

Answer 12

That the angle to the normal is the same size

Question 13

What is refraction?

Answer 13

Is the change of direction of a ray light as it moves from one material to another

Question 14

Why refraction happens?

Answer 14

Because there is a change in speed for one material to another

Question 15

What happens to light when it passes through a glass block?

Answer 15

That the refracted ray it bends towards the normal

Question 16

Where refraction occurs?

Answer 16

In transparent surfaces

Question 17

What is a critical angle?

Answer 17

When the angle of refraction is 90* the angle of incidence is called critical angle and the refracted ray runs along the surface/boundary.

Question 18

What is the total internal reflection?

Answer 18

Is the angle of incidence that is bigger than the critical angle all the light is reflected and no light is refracted ( only occurs when light passes from a more dense to a less dense medium e.g=from glass to air)

Question 19

What is white light?

Answer 19

White light=is a mixture of many different colors in different frequencies and can be split up into a spectrum of this colors using a prism and light
When light enters the prism you can see each color is refracted by different amounts
This means that the light leaving the prism is spread out into different colors, this process is called DISPERSION

Question 20

What is the spectrum?

Answer 20

Are seven colors listed in order so their frequency

From lowest to highest frequency

Question 21

Why some objects appear colored?

Answer 21

When light hits a surface, some of it can be absorbed and some of it reflected.
The light that is reflected is the color of the object and all the other colors are absorbed

Question 22

How filters can be used to make colored light?

Answer 22

The filter will just let us see the object behind it in black or the color of the filter because just transmits its color

Question 23

How specialized cells in the eye (CONES) enable us to perceive color?

Answer 23

They only work when the light is bright enough, but not when light is very dim
Are responsible for color vision
There are three types of color vision: blue, green and red
This is why we can’t see colors at night when the light is very dim(Rods)
Rods are responsible for night vision and any let us see in black, white and grey

Question 24

How images are formed by lenses in our eyes?

Answer 24

Convex lens focus the image on the retina by refracting light, producing an inverted image.
The retina contains cells that are sensitive to light, so they produce electrical impulses when they absorb light the impulses are passed along the optic nerve to the brain, which interprets them
Finally, the brain intercepts the image that right way around

Question 25

What is a concave lens?

Answer 25

Is thinner in the middle than at the edges, which causes parallel rays to diverse
People that are short sighted can’t see things that are far away

Question 26

What is a convex lens?

Answer 26

Is thicker in the middle than is at the edges.
Parallel light rays that enters the lens CONVERGE (come together at a pinto called the principal focus
People who are long sighted can’t see objects nearby