eyes

Question 1

What is the difference between converging and diverging lens?

Answer 1

If both sides of the lens curve outward, it is called a converging lens, and it will bend light from distant objects inwards toward a single point, called the focal point. If both sides of the lens curve inward, it is called a diverging lens, and light from distant objects will bend outwards.

Question 2

What are real and virtual images?

Answer 2

A real image is formed by the actual intersection of light rays whereas a virtual image is formed by the imaginary intersection of light rays. A real image can be formed in in a screen but a virtual image can be only seen in the mirror.

Question 3

Use the principles of refraction to explain why objects appear different underwater.

Answer 3

Refraction of light in water — Science Learning Hub
When light travels from air into water, it slows down, causing it to change direction slightly. This change of direction is called refraction.

Question 4

Explain how we see colour.

Answer 4

Light travels into the eye to the retina located on the back of the eye. The retina is covered with millions of light sensitive cells called rods and cones. When these cells detect light, they send signals to the brain. Cone cells help detect colors.

Question 5

What parts of the eye will a light ray pass through to strike the retina?

Answer 5

Some of this light enters the eye through an opening called the pupil (PYOO-pul). The iris (the colored part of the eye) controls how much light the pupil lets in. Next, light passes through the lens (a clear inner part of the eye). The lens works together with the cornea to focus light correctly on the retina

Question 6

eye disease

Answer 6

Cataract

Question 7

cataract

Answer 7

Cataracts are when the lens, a small transparent disc inside your eye, develops cloudy patches. Over time these patches usually become bigger causing blurry, misty vision and eventually blindness.

Question 8

lable eyes

Answer 8

Cornea
Pupil
Iris
Lens
retina
Optical nerve
sclera
liquad humor

Question 9

cornea meaning

Answer 9

Clear window, refracts light, helps to focus the light

Question 10

Pupil

Answer 10

Hole in the iris, which allows light to enter the eye

Question 11

Iris

Answer 11

Coloured, changes size to control the amount of light entering the eye

Question 12

Lens

Answer 12

Refracts light to focus image on the retina. Focal length adjusted by ciliary muscles

Question 13

Retina

Answer 13

Light sensitive cells (rods & cones) which change light energy to nerve impulses.

Question 14

Optical nerve

Answer 14

Takes messages from the retina to the brain

Question 15

Sclera

Answer 15

The white, tough outer layer that protects the eye. Choroid: black layer of blood vessels.

Question 16

Liquid humour

Answer 16

Watery at the front, jelly at the back, helps to keep eye’s shape and provide medium for light to travel through.