Book 4, Question 79 · Video
Why Does Thunder Follow Lightning?
Lightning is a giant spark! It heats the air so fast that the air explodes outward. That shock wave is thunder. About 5 seconds between flash and boom means the storm is roughly 1
Read the full answer →What Crafty Clover says in this video
Intro
Hey there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why does thunder follow lightning?
The Big Idea
Lightning is a giant spark! It heats the air so fast that the air explodes outward. That shock wave is thunder. And light is much faster than sound.
Charge Builds, Spark Jumps
Step one: charge builds, and a spark jumps. Inside a storm cloud, bits of ice bump around and separate electric charge. When the charge gets big enough, a giant spark jumps. That's lightning. That spark heats the air around it in a split second.
Air Explodes
Step two: the air explodes outward. The air around the spark gets hotter than the surface of the sun, and it expands so fast that it makes a shock wave. That shock wave is the sound we call thunder.
Light, Then Sound
Step three: light arrives first, and sound arrives later. Light travels almost instantly, so you see the flash first. Sound is much slower, so the thunder rolls in later. It takes sound about 5 seconds to travel a mile. A longer wait means the storm is farther away.
A Closer Look
Let's take a closer look at the lag! The flash jumps from the storm cloud, and the light reaches you almost at once. The sound travels slowly, so it arrives after a wait. Counting the seconds between them gives you a rough distance.
Quick Facts
Quick facts! About 5 seconds between flash and boom means the storm is roughly 1 mile away. If you can hear thunder, lightning is close enough to be dangerous. Buildings and cars with hard tops are safer than fields and trees. Stay inside until 30 minutes after the last boom.
Think Like a Scientist
Now, think like a scientist! From a safe window, time the gap from flash to boom. Did the wait get shorter or longer? What does a shorter wait mean? Stay indoors until the storm is long gone, and wait for the all clear.
Outro
See the flash, count the seconds, and stay safe indoors! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!