Science / Grade 1
Where light comes from
Learning goal: Follow light from a glowing source to an ordinary object and then into the eye. Distinguish making light from reflecting it.
Before you start: Recognize a lamp, a book and an eye. An adult can read the labels. Use the pictures only; no equipment or outdoor observation is needed.
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Next: your worksheet
Separate Light Sources from Reflectors - Practice 1
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Video transcript and practice. Reading or printing does not count as playback time or an assessed grade.
1. Who makes the light?
Video: 0:00
Here is a lamp that is on. Here is a book beside it. We can see both. But do both make light? The lamp makes light. The book does not make its own light. A book with a story about stars is still not a star! Let us follow where the light goes.
2. Start at the source
Video: 0:22
The glowing lamp is a light source. A source makes light and sends it out. Emit is another word for send out. Light from the lamp can travel straight to an eye. The arrow points from the lamp toward the eye. We use pictures here. Never look straight at the Sun or a very bright lamp.
3. How do we see the book?
Video: 0:45
Some light from the lamp reaches the book. The book sends some of that light in a new direction, toward our eyes. That is called reflection. Follow the path: lamp, then book, then eye. Light enters the eye. Our eyes do not shine a seeing beam onto the book. They receive light.
4. Not just a mirror
Video: 1:08
A mirror reflects light. So does an ordinary sheet of paper. So does a plain toy block. You do not need to see your face in something for it to reflect light! In our picture, the lamp lights all three objects. Each reflects some of that light. None of these three objects makes its own light.
5. Pause: lantern and block
Video: 1:32
Your turn. A lantern is on and glowing. Its light reaches a plain wooden block. You can see the block. Which makes light: the glowing lantern or the wooden block? How does light reach your eyes from the block? Pause and explain. An adult can listen to your answer. You do not need a real lantern.
6. Check the light path
Video: 1:58
The glowing lantern makes light. It is the source. The block reflects some light toward your eyes. Say the path: lantern, then block, then eye. If you chose the block as the source, try again. Being easy to see does not mean making light. Our wooden block has not secretly become a tiny lamp!
7. The Moon borrows its glow
Video: 2:22
Fun fact: the Moon does not make its own visible light like the Sun. The Moon looks bright because it reflects sunlight. Think of our book and lamp. A bright-looking object can be reflecting light from somewhere else. You do not need to go outside for this lesson. Never look straight at the Sun.
8. Continue to the worksheet
Video: 2:44
Now try the worksheet below. In each question, ask: does this thing make its own visible light, or does it reflect light from somewhere else? Read what is happening. A screen that is on and glowing makes light. An ordinary page lit by a lamp reflects it. An adult can read with you. Try Practice Two next, on screen or on paper.
Show your understanding
You can point, explain aloud, draw or write.
- Distinguish an object making its own visible light from one reflecting light in a stated situation.
- Explain the path from a light source to an ordinary object and then into the eye; apply it to a fresh lantern example and both worksheets.
Try it yourself
Pause at the glowing lantern and wooden block. Name what makes light, then explain how light reaches your eyes from the block.
Continue to the worksheet, then Practice Two. Read what is happening before choosing source or reflector. An adult can read with you.
Next: your worksheet
Separate Light Sources from Reflectors - Practice 1https://s3u.com/sr1ae
Practice Two: more light sources and reflectors · Practice following light
Lesson: https://s3u.com/lessons/where-light-comes-from