Chapter 1: Light&Eye

Question 1

What is a light wave also known as?

Answer 1

Light rays

Question 2

What is specular reflection?

Answer 2

When all light reflects off at the same angle and directions, only on smooth surfaces

Question 3

What is diffuse reflection?

Answer 3

Only happens on rough surfaces, the light is reflected in scattered directions and angles

Question 4

What’s the law of reflection?

Answer 4

The angle of incidence is always equal to the angle of reflection

Question 5

What is refraction?

Answer 5

When light bends as it crosses a boundary

Question 6

What will light only travel through?

Answer 6

Transparent material, not anything opaque

Question 7

What’s a medium?

Answer 7

Any substance that light travels through

Question 8

Which way does light bend when going from a less dense medium to a more dense medium?

Answer 8

Towards the normal(e.g: glass to air)

Question 9

Which way does light bend when it goes from a more dense medium to a less dense medium?

Answer 9

Away from the normal

Question 10

What happens in refraction?

Answer 10

Light hits the “glass” at an angle, slows down and bends, the Ray bends towards the normal and speeds up at the same angle

Question 11

Why do we see thing?

Answer 11

Because of reflection, when luminous objects produce light it’s reflects off non-luminous objects, it reflects into our eyes

Question 12

Function of pupil?

Answer 12

Let’s light in

Question 13

Function of ciliary muscle?

Answer 13

Adjusts the focus by pulling the lens thin or squashing it fat

Question 14

Function of iris?

Answer 14

Determines how much light gets in

Question 15

Function of retina?

Answer 15

Contains photoreceptor cells that detect dim light(rods) or colour (cones)

Question 16

Function of the cornea and lens?

Answer 16

Refracts/reflects light

Question 17

What’s the nerve that sends messages to brain from eye?

Answer 17

Optic nerve

Question 18

What does long-sighted mean?

Answer 18

Can’t see things that are closer so your lens focuses behind the retina

Question 19

What does short-sighted mean?

Answer 19

Can’t see things far away so lens focuses before retina

Question 20

Colours of rainbow in order

Answer 20

Red
Orange
Yellow
Green
Blue
Indigo
Violet

Question 21

How do we see white light?

Answer 21

No colours are absorbed and all reflected

Question 22

How do we see black light?

Answer 22

All colours are absorbed and none are reflected?

Question 23

How do we see a particular colour? For example blue

Answer 23

Blue light is reflected and the rest are absorbed

Question 24

What are shadows?

Answer 24

Places where light is blocked

Question 25

How does light travel

Answer 25

Straight lines