Let’s go through each question one by one and think about what we know about light waves and sound waves.
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1. Electromagnetic Waves:
Electromagnetic waves are waves that can travel through empty space (like in space or a vacuum). Light is an example of this — it doesn’t need air or water to move. Sound, on the other hand, needs something to vibrate — like air, water, or solids. So:
✔ Light
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2. Mechanical Waves:
Mechanical waves need a medium (something physical) to travel through — like air, water, or metal. Sound is a mechanical wave because it moves by making particles bump into each other. Light does NOT need a medium — so it’s not mechanical.
✔ Sound
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3. Which waves travel faster?
Light travels super fast — about 300,000 kilometers per second in a vacuum! Sound is much slower — only about 343 meters per second in air. That’s why you see lightning before you hear thunder.
✔ Light
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4. Which waves require a medium to travel?
As we said earlier, sound needs air, water, or solid stuff to move. Light can go through nothing at all — like outer space.
✔ Sound
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5. True or False… Sound waves can travel through a vacuum.
A vacuum means no air, no molecules — nothing to vibrate. Since sound needs something to vibrate, it CANNOT travel through a vacuum. Think of space — it’s silent because there’s no air for sound to move through.
✔ False
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6. True or False… During a thunderstorm, what happens first? You hear thunder and then see the lightning strike. OR You see lightning strike and then hear thunder.
We already know light travels way faster than sound. So when lightning strikes, you SEE it almost instantly. The sound (thunder) takes longer to reach your ears. So you always see lightning first, then hear thunder.
✔ You see lightning strike and then hear thunder.
*(Note: This isn’t technically “True or False” as written — but since it asks which happens first, we pick the correct sequence.)*
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7. What type of medium do sound waves travel fastest through?
Sound travels slowest in gases (like air), faster in liquids (like water), and FASTEST in solids (like steel or wood). Why? Because particles in solids are packed tightly together — they bump into each other quickly, passing the vibration along faster.
✔ Solid
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Final Answer:
1. Light
2. Sound
3. Light
4. Sound
5. False
6. You see lightning strike and then hear thunder.
7. Solid
Parent Tip: Review the logic above to help your child master the concept of waves sound and light worksheet.
