light and optics unit test

Question 1

what is the angle of incidence?

Answer 1

angle between incident ray and the normal

Question 2

what is the angle of reflection?

Answer 2

angle between the normal and the reflected ray

Question 3

what is the angle of refraction?

Answer 3

angle between normal and refracted ray

Question 4

concave means…

Answer 4

to curve inwards

Question 5

what are cones?

Answer 5

located in the retina
they are cone shaped cells that detect colour

Question 6

convex means…

Answer 6

to curve outwards

Question 7

what is the incident ray?

Answer 7

the ray of light that strikes a reflecting or refracting material

Question 8

what is the iris?

Answer 8

located in the eye
It is the coloured ring
works like the diaphragm of a camera

Question 9

what is an iris reflex?

Answer 9

the natural adjustment in the eyes’ pupil/size in response to varying light levels

Question 10

what are the laws of reflection?

Answer 10

they are the 2 main predictable behaviours of reflected light
1. the angle of reflection is = to the angle of incidence
2. Incident ray, the normal, and the reflected ray are all always in the same plane

Question 11

what is a lens?

Answer 11

a cured piece of transparent material, usually glass or plastic that bend light rays as they pass through it.

Question 12

what is light?

Answer 12

the form of energy we can see. It can be bent or curved in specific circumstances/situations.

Question 13

what is the normal?

Answer 13

a reference line drawn perpendicular to a reflecting surface at the point where an incident ray strikes the surface

Question 14

what does opaque mean?

Answer 14

a substance/material tha does NOT allow any light to pass through
works opposite to transparent and transluscent materials

Question 15

what is a pupil?

Answer 15

the opening in the eye; appears as the dark center of the eye
acts as the passage way where light enter the eye from

Question 16

what is a ray?

Answer 16

a single line or narrow beam of light that that originates from a light source and may bounce off from a surface that it strikes

Question 17

what is a ray diagram?

Answer 17

a representation of the path of light by using a straight line with an arrow

Question 18

what is a reflected ray?

Answer 18

the light that is cast back (reflected) from a reflecting surface

Question 19

what is a reflecting telescope?

Answer 19

a telescope that has a concave mirror to collect the rays of light from a distant object

Question 20

reflection means…

Answer 20

the casting back of light from a surface

Question 21

what is a refracting telescope?

Answer 21

telescope that has a convex lens to collect and focus light from a distant object and an eyepiece lens to magnify it

Question 22

refraction means…

Answer 22

the bending of light when it travels from one medium of a certain density to another

Question 23

what it the retina?

Answer 23

a light sensitive area at the back of the eye

Question 24

what are rods?

Answer 24

located in the retina
a cylinder like cell that detects the presence of light

Question 25

transluscent means...

Answer 25

allowing some light to pass throughtbut the light is scattered from its straight path

Question 26

transparent means...

Answer 26

allowing light to pass through

Question 27

what are the 4 properties of light?

Answer 27

1. light travels in straight lines 2. light can be reflected 3. light can be refracted 4. light is a form of energy

Question 28

bioluminescent light is...

Answer 28

light produced in living creatures ex. jellyfish

Question 29

fluorescent light is...

Answer 29

glow caused by absorbtion of high energy UV light ex. fluorescent mercury vapor lamp

Question 30

chemiluminescent light is...

Answer 30

when a chemical reaction produes visible light energy ex. glow sticks

Question 31

phosphorescent light is...

Answer 31

similiar to fluorescent light, however visible light is emmited over an extended period of time ex. glow in the dark stickers

Question 32

incandescent light is...

Answer 32

emmision of visible light by hot objects ex. light bulb

Question 33

properties of a concave mirror

Answer 33

it curves inwards produces and inverted image from afar but when brought closer it is magnefied ex. scoop side of spoon

Question 34

properties of a convex mirror

Answer 34

it curves out produces a small and upright image ex. back of a spoon

Question 35

properties of a plane mirror

Answer 35

flat surface produces a mirror image ex. normal flat mirror

Question 36

rules of a convex lens

Answer 36

1. a ray of light which is parallel to the principle axis, after refraction passes through the focus on the other side of the lens 2. a ray of light passing through the optical center of the lens goes straight. It emerges without deviation 3. a ray of light passing throught the focus after refraction becomes parallel to the principle axis

Question 37

rules of a concave lens

Answer 37

1. a ray of light which is parallel to the principle axis after refraction appears to be coming from the focus 2. a ray of light going toward the optical center of a concave lens goes straight through without being deviated 3. a ray of light going towards the focus after refraction becomes parallel to the principle axis

Question 38

what is the pupil?

Answer 38

part of the eye that lets light in

Question 39

what is the optic nerve?

Answer 39

photoresceptors send image through optic nerve to the brain

Question 40

what is the cornea?

Answer 40

transparent layer infront of eye over pupil

Question 41

what is the sclera?

Answer 41

white felsh of eye

Question 42

aqueous humor is the...

Answer 42

clear liquid between cornea and lens resembling water

Question 43

virtuos humor is the...

Answer 43

jelly like substance filling rest of the eye

Question 44

what are the ciliary muscles?

Answer 44

help push and pull lens into place to help focus images

Question 45

nearsightedness is when...

Answer 45

light converges at a point infront of retina

Question 46

farsightedness is when

Answer 46

light converges at a point beyond retina