Optics

Question 1

What is light?

Answer 1

A form of electromagnetic radiation and travels in waves

Question 2

What is the electromagnetic spectrum?

Answer 2

A way to measure light in different frequencies. The wavelengths range from 0.00001nm to 500nm. The longest is radio waves and the shortest is gamma rays.

Question 3

How many categories is light split into?

Answer 3

Two main categories and four subcategories.

Question 4

Incandescence is?

Answer 4

Light energy released by heat. Solids heated til they release light. (Hot metal, sun, fire and old lightbulbs.)

Question 5

What’s luminescence?

Answer 5

Light energy released by electrons moving levels.

Question 6

Fluorescence is?

Answer 6

Absorbs energy, re-emits as light. (Neon lights)

Question 7

Bioluminescence is?

Answer 7

Light from living things (jellyfish, algae, firefly and anglerfish.)

Question 8

Phosphorescence is?

Answer 8

Absorbs light lengths (shorter) releases longer wavelengths as light. (Glow in the dark)

Question 9

What does the cornea do?

Answer 9

It’s clear like a window and helps focus incoming light.

Question 10

What does the pupil do?

Answer 10

It’s an opening in your eye. (The black part.)

Question 11

What does the iris do?

Answer 11

It’s the coloured part of your eye and controls the size of your pupil, it makes the pupil bigger when it’s dark to allow more light through. Makes the pupil smaller when it’s bright to let less light in.

Question 12

What does the lens do?

Answer 12

It focuses oncoming light into your eye, thins and thickens to help you see things far and near.

Question 13

What are your colour receptors called?

Answer 13

Rods and cones. Which are located in the retina

Question 14

What do rods do?

Answer 14

Help us see in low light

Question 15

What do cones do?

Answer 15

They detect red, green and blue

Question 16

What does the retina do?

Answer 16

The image is projected onto the retina and flipped upright then transmitted to the optic nerve.

Question 17

What does the optic nerve do?

Answer 17

It transfers the image to your brain

Question 18

What are the light detecting cells called?

Answer 18

Photoreceptors.

Question 19

What is the thin layer in the back of the eye?

Answer 19

Retina

Question 20

What is the oval part of the eye?

Answer 20

The lens

Question 21

What is the connection to the brain?

Answer 21

The optic nerve

Question 22

What is the thin layer in the front of the eye?

Answer 22

The cornea

Question 23

What is the hole in middle of the eye?

Answer 23

The pupil

Question 24

What are the things surrounding the hole in the eye?

Answer 24

The iris

Question 25

What are the primary additive colours?

Answer 25

Red, green and blue

Question 26

What are the secondary colours?

Answer 26

Yellow, cyan and magenta

Question 27

What do you get when you mix red and green?

Answer 27

Yellow

Question 28

What do you get when you mix red and blue?

Answer 28

Magenta

Question 29

What do you get when you mix blue and green?

Answer 29

Cyan

Question 30

What does cyan, magenta and yellow make?

Answer 30

Black

Question 31

What does yellow, red and blue make?

Answer 31

White

Question 32

What colours are used in the TV screen?

Answer 32

Red, green and blue

Question 33

What are the colours of the visible colour spectrum in order? (Longest to shortest)

Answer 33

Red, orange, yellow, green, blue and violet

Question 34

How does the angle of incidence and reflection work with mirrors?

Answer 34

When light hits the mirror at angle it bounces off at the opposite angle. The angle of incidence to the angle of reflection.

Question 35

How would you appear in a concave mirror?

Answer 35

Upside down

Question 36

How would you appear in a convex mirror?

Answer 36

Puffed out and weird.

Question 37

What happens when light passes through a double concave lens?

Answer 37

It spreads out

Question 38

What happens when light passes through a double convex lens

Answer 38

It focuses the light to the focal point.

Question 39

How does a concave lens help nearsightedness?

Answer 39

When it hits the eye it focuses it in then immediately spreads it to the flipped image at the back of the eye after it hits the focal point.

Question 40

How does a convex lens help farsightedness?

Answer 40

It focuses the light onto the image at the back of the eye.