What Makes Thunder? | Easy Science Reading

This short science reading passage is for English learners. Read the passage, learn key vocabulary, and answer the questions.

Thunder is the sound made when lightning heats air quickly.

Reading Level

A2-B1

Word Count

287 words

Reading Passage

Thunder is the loud sound we hear during a storm. It often comes after a flash of lightning. Thunder and lightning are closely connected.

Lightning is a very strong spark of electricity in the sky. When lightning moves through the air, it heats the air around it very quickly. The air becomes extremely hot for a very short time.

Hot air expands. This means it suddenly grows larger and pushes outward. The fast expansion makes a strong movement in the air. That movement creates sound waves.

Those sound waves travel to our ears, and we hear thunder. If lightning is close, thunder can sound very loud and sharp. If lightning is far away, thunder may sound low and rolling.

We usually see lightning before we hear thunder. This happens because light travels much faster than sound. The flash reaches our eyes almost immediately, but the sound takes longer to reach our ears.

People sometimes count the seconds between lightning and thunder. More seconds usually mean the lightning is farther away. However, storms can be dangerous, so it is safest to go indoors when thunder is heard.

Thunder is not a separate thing from lightning. It is the sound made when lightning heats air and the air expands quickly.

A storm may seem mysterious, but thunder has a clear science explanation: electricity, heat, moving air, and sound.

Lightning heats air, the air expands, and sound waves make thunder.

Key Vocabulary

Word	Meaning	Example
thunder	the loud sound heard during a storm	Thunder followed the lightning.
lightning	a bright flash of electricity in the sky	Lightning heated the air quickly.
expand	to become larger	Hot air expands quickly.
sound waves	waves of moving air that our ears hear as sound	Sound waves carry thunder to our ears.
storm	bad weather with strong wind, rain, thunder, or lightning	We went inside during the storm.

Reading Comprehension Questions

1. What is thunder?
2. What heats the air during a storm?
3. What happens when hot air expands quickly?
4. Why do we see lightning before hearing thunder?
5. What should people do when they hear thunder?

Answers

1. Thunder is the loud sound heard during a storm.
2. Lightning heats the air.
3. It creates sound waves.
4. Light travels faster than sound.
5. They should go indoors because storms can be dangerous.

Short Summary

Thunder happens when lightning heats air very quickly. The hot air expands, creates sound waves, and those waves travel to our ears.

More Easy Readings

• How Are Rainbows Made?
• Why Do We Have Seasons?