Light

Question 1

What is the angle of incident equal to?

Answer 1

The angle of reflection

Question 2

What is total internal reflection? (TIR)

Answer 2

When no light passes from the glass into the air

Question 3

What is the critical angle for TIR?

Answer 3

42°

Question 4

What is refraction?

Answer 4

When no light passes from one medium to another

Question 5

What changed during refraction?

Answer 5

The speed of light, usually changed direction

Question 6

What happens when light enters a more dense material?

Answer 6

It slows down

Question 7

What happens when light enters a less dense material?

Answer 7

It speeds up

Question 8

What is an example of refraction going to one medium to another?

Answer 8

Air to glass

Glass to air

Question 9

What is the normal?

Answer 9

The point which is at a right angle to the surface

Question 10

What would happen is light was to travel through air to glass?

Answer 10

It would slow down because it is entering a more dense material

Question 11

What is white light made up from?

Answer 11

Red, orange, yellow, green, blue, indigo and violet (the colours of the rainbow)

Question 12

When do all the individual colours of the rainbow show?

Answer 12

When white light refracts

Question 13

Describe application

Answer 13

When light from the sun appears white, but is refracted through water droplets in the atmosphere, you can see the colours of the rainbow

Question 14

What are the primary colours of light?

Answer 14

Red, green and blue

Question 15

What is dispersion?

Answer 15

When a prism splits a ray of white light into all the colours of the rainbow

Question 16

What colour is most refracted?

Answer 16

Violet (think ULTRA violet)

Question 17

What light is least refracted?

Answer 17

Red light

Question 18

How many colours can light be split into?

Answer 18

7

Question 19

What splits colours?

Answer 19

Prisms

Question 20

What do lenses do?

Answer 20

Reflect parallel beams of light so that they bend away or towards each other

Question 21

What are the two main types of lenses?

Answer 21

Convex and concave

Question 22

What does a concave do to the rays?

Answer 22

It makes them spread out

Question 23

What are pupils?

Answer 23

Basically holes in our eyes that allow in light, the size and diameter change depending on the light levels

Question 24

In humans, where does light enter?

Answer 24

Through the cornea and pupils

Question 25

How does the brain receive images?

Answer 25

By the cornea and the lens focusing light onto the retina and the optic nerve carries the information to the brain

Question 26

What happens when we look at an object close up?

Answer 26

The lens becomes fatter, more powerful

Question 27

What happens when we look at a distant object?

Answer 27

The lens becomes thinner, less powerful

Question 28

A converging lens = ?

Answer 28

A positive focal point and a positive power

Question 29

A diverging lens = ?

Answer 29

A negative focal point and a negative power

Question 30

Do convex lenses have a positive or negative effect?

Answer 30

Positive

Question 31

How do we measure the focal length of a convex lens?

Answer 31

We measure between the normal and the focal point