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Lesson 1

Are all light sources the same?

Key Knowledge Key Vocabulary

• Objects that give out light are called sources of light

• Light travels from a source

• Sources of light vary in brightness

• Light sources can be natural or man-made

• Darkness is the lack of light

• source

• emit

• vary

• natural

• man-made

What is a light source? Are all light sources the same?

Friday 8th January 2021 Science

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What is light?

Any object that emits light is called a light source. A wave of light can only travel in a straight line. Without light, it is completely dark and we cannot see the world around us. When you enter a dark room and turn on the light, you can see everything in that room.

Our main source of natural light on Earth comes from the Sun. Some light sources are natural, like the Sun, and some are man-made like lamps, bulbs and torches. Light sources vary in brightness- some are much brighter than others. Animals like fireflies and glow worms are natural sources of light. They emit their own light to attract mates.

A ray of light travels very fast. In the time it takes you to blink your eyes three times, light could travel to the moon and back! It takes just over 8 minutes for light to travel from the Sun to Earth a distance of 93 million miles. It is the fastest thing in the universe! Nothing else travels faster than light, not even sound, which is why you hear the thunder after you see the lightning during a storm.

Where does our main source of natural light come from?

Give 2 examples of man-made light sources.

What is darkness?

What do you know about how fast light travels?

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First, decide whether these items are light sources or not. Then, sort the light sources into natural or man-made.

Natural

Something which occurs naturally or is in the environment (e.g. the Sun)

Man-made

Something which is created by humans

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Is this window a light source? Explain how you know?

Is this natural or man-made? Explain your answer.

Explain why the moon is not a light source.

Friday 8th January 2021 Year 3 - French Les parties du corps - Body parts Le bras La jambe Le pied Le ventre Le dos Le genou L’épaule La main Le doigt Le nez La tête Les yeux La bouche L’oreilles Le cou Les cheveux Using the table above, write down the body parts using c’est or ce sont. The first 2 have been done for you. Qu’est-ce que c’est ?