Optics

Question 0

Non-luminous

Answer 0

Does not produces its own light but reflects light in order to be seen. (eg: The Moon)

Question 1

Luminous

Answer 1

Produces its own light (eg: The Sun)

Question 2

Transparent Object

Answer 2

Fully allows light to pass through (eg: clear glass)

Question 3

Translucent Object

Answer 3

Partially allows light to pass through (eg: bathroom window glass)

Question 4

Opaque Object

Answer 4

Does not allow light to pass through (eg: Metal)

Scattering of Light

Question 5

To have a clear sight the image must be …?

Answer 5

Focused on the retina.

Question 6

A thick lens = shorter or longer focal length?

Answer 6

Shorter

Question 7

A thin lens = shorter or longer wavelength?

Answer 7

Longer

Question 8

To cater for viewing far objects and close objects what doe dthe lens do?

Answer 8

It changes shape between thick and thin.

Question 9

If the lens is unable to change shape to focus on a far or near object, then what happens to the image?

Answer 9

It becomes blurred

Question 10

Short sighted

Answer 10

Can’t see far objects

Question 11

Long sighted

Answer 11

Can’t see near objects

Question 12

What lens is needed to fix short sighted-ness?

Answer 12

A concave lens

Question 13

Why is a concave lens needed to fix short sighted-ness?

Answer 13

Because before the light reaches the eye it diverges the rays so before it enters the eye it’s more spread out, so it doesn’t bend before it reaches the retina.

Question 14

What lens is needed to fix longsightedness?

Answer 14

Convex lens

Question 15

Why is a convex lens needed to fix longsightedness?

Answer 15

Because a convex lens converges the light before it reaches the eye, so when it goes into the eye it has already begun bending and can help the eye do it, so it doesn’t go past the retina.

Question 16

What does the iris do?

Answer 16

It controls the diameter and size of the pupil and the amount of light that reaches the retina.

Question 17

What does the cornea do?

Answer 17

Covers the iris and pupil and helps to keep the eye clean from dirt and germs.

Question 18

What does the pupil do?

Answer 18

Controls the amount of light reaching the retina by enlarging or reducing its size.

Question 19

What does the lens do?

Answer 19

Focuses the image by bending the light to hit the retina correctly. (Refraction) it changes shape to change the focal distance of the eye so it can focus on objects at different distances.

Question 20

What does the vitreous gel do?

Answer 20

It’s a gel that fill most of the eyeball. It enables the eye to hold its round shape and holds some parts of the eye in place, it stops the eye from collapsing.

Question 21

What does the optic nerve do?

Answer 21

Carries signals from the retina to the brain so it can interpret them.

Question 22

What does the retina do?

Answer 22

Receives the image seen through the eye, upside down. Then it sends it to the brain via the optic nerve where it is put straight

Question 23

Do convex lens converge or diverge?

Answer 23

Converge

Question 24

Do concave lens converge or diverge?

Answer 24

Diverge

Question 25

What is the numerical form of 1 x 10m to the power of -2?

Answer 25

0.01m

Question 26

What appears to have happened to your foot when you look at in while in the swimming pool?

Answer 26

Your foot looks closer/higher than it really is