light

Question 1

Name three ways in which list can be produced.

Answer 1

1. Naturally
2. Artificially
3. By chemical reactions

Question 2

light is produced naturally by two things. Name these two things.

Answer 2

1) the sun

2) fire

Question 3

How can light be produced artificially.

Answer 3

By using electricity

Question 4

explain how chemical reactions produce light.

Answer 4

It occurs when fireflies produce their light when chemical reactions occur in their bodies

Question 5

Explain what are luminous objects and give an example

Answer 5

They are objects that generate their own light and they have their own source of energy

Example : sun , stars and a light bulb.

Question 6

Explain what is a non- luminous object and give an example

Answer 6

They are objects that receive light from a luminous source and then reflects it
Example : the moon

Question 7

List and explain 6 properties of light.

Answer 7

7.1. Light is a form of energy

Light is the only way energy can be transferred through space
An object becomes warm when placed in the sun because it absorbs the suns energy

7.2. Light travels at 300 000 km/s

Only light can travel at this speed , this is the speed limit of the universe
The distance from the sun to the earth is 150 million km , light takes about 8 1/2 min to reach earth

7.3. Light travels in straight lines

Shows of objects show the sae online shape and the object themselves , this because line travels in straight lines

7.4. You can only see when light from an object enters your eyes

Light rays have to strike the the inside of your eye to enable you to see

7. 5. As you move away from the light source its intensity decreases
8. 6. Light an be reflected , refracted (bent), transmitted (passed through) or absorbed

Question 8

List, explain an give examples of the 3 terms associated with light

Answer 8

8.1. Transparant

These materials allow all the light to pass through them so that you can easily see what on the other side
Example : glass ,water, air

8.2. Opaque

A shadow is formed when a opaque object blocks the path of light
Light travels n straight path an cannot bend so therefore it creates a shadow

8.3 Translucent

Allow light to pass through but you can’t see through them
Example :frosted bathroom window ,paper