Light And The Eye

Question 1

Angle of incidence

Answer 1

The angle an incoming Ray makes with the normal

Question 2

Angle of reflection

Answer 2

The angle a reflected Ray makes with the normal

Question 3

Diffuse reflection

Answer 3

Reflection of light in many directions from an uneven surface, such as a book or a backpack

Question 4

Incident Ray

Answer 4

Incoming Ray

Question 5

Law of reflection

Answer 5

i=r or the law stating that light is reflected at the same angle that it is incident

Question 6

Normal

Answer 6

An imaginary line that is drawn at right angles to a surface that light is incident a
Upon

Question 7

Plane mirror

Answer 7

A flat mirror

Question 8

Refraction

Answer 8

The bending of light as it enters or leaves different substances

Question 9

Refractive index

Answer 9

A measure of how easily light travels through a substance

Question 10

Regular reflection

Answer 10

Reflection of light from a very smooth surface, such as still water or a mirror; it produces a clear image

Question 11

Total internal reflection

Answer 11

When light is Completely reflected from the boundary of two substances; it occurs when the angle of incident is great than the critical angle

Question 12

Critical angle

Answer 12

The angle of incidence of light that produces an angle of refraction of 90 degrees

Question 13

Conduction

Answer 13

A method of heat transfer in which heat is passed by vibration of particles

Question 14

Conductor

Answer 14

A substance that allows heat to flow through it

Question 15

Insulator

Answer 15

A material that doesn’t conduct heat

Question 16

Concave lens

Answer 16

Lens that curves inwards

Question 17

Convex lens

Answer 17

A lens that bulges out wards

Question 18

Cornea

Answer 18

A transparent covering over the iris of the eye; it bends light into the lens

Question 19

Focal length

Answer 19

The distance from a lens to its focus

Question 20

Lens

Answer 20

In the eye it is a flexible structure that enables light to be focused on the retina

Question 21

Another name for long sightedness

Answer 21

Hyperopia

Question 22

Long sightedness

Answer 22

The inability to focus on close objects because the eyeball is too long

Question 23

Optic nerve

Answer 23

A nerve that carries an electrical signal from the retina to the brain

Question 24

Real image

Answer 24

An image formed when Ray’s of light do actually meet

Question 25

Retina

Answer 25

Nerve tissue at the back of the eye, consisting of cone cells and rod cells; light is converted into an electrical signal here

Question 26

Short sightedness

Answer 26

The inability to focus on distant objects because the eyeball is too short

Question 27

Accomodation

Answer 27

The ability of the lens of the eye to change its shape to adjust its focus

Question 28

Aqueous humour

Answer 28

Lies between the cornea and the lens . | It is a clear, watery fluid produced by the ciliary body to lubricate the lens and cornea

Question 29

Cornea

Answer 29

Bends light into the lens Lies in front of the iris Is clear

Question 30

Ciliary body

Answer 30

The lens is connected to the ciliary body | Muscles in the ciliary body change the shape of the lens

Question 31

Conjunctiva

Answer 31

A membrane that covers the sclera

Question 32

Choroid

Answer 32

Has a rich blood supply and nourishes the retina

Question 33

Sclera

Answer 33

White of the eye

Question 34

Cone cells and rod cells are

Answer 34

More concentrated in the fovea centralis - the sharpest vision Rod cells are located in the retina

Question 35

Fovea centralis

Answer 35

Responsible for sharp central vision

Question 36

Eye muscles

Answer 36

Enable the eye to rotate in its socket

Question 37

Vitreous humour

Answer 37

Clear fluid between the lens and retina

Question 38

Dilator muscle

Answer 38

Enlarges the Pupil, allowing more light in the eye

Question 39

Sphincter muscle

Answer 39

Makes the pupil smaller, which stops light entering the eye

Question 40

Iris

Answer 40

The coloured part of the eye | It contains the dilator muscles and sphincter muscle as part of its structure

Question 41

Pupil

Answer 41

An opening in the iris that determines the amount of light entering the eye