Thunder has always captured our imagination. In ancient times, people thought it might be the sound of a young god’s anger, the rumbling of Thor’s chariot, or even the flapping wings of a giant bird. But thanks to science, we now know what thunder really is and why it sounds the way it does.
During a storm, there are a lot of things happening. One important thing is the buildup of positively and negatively charged particles in the clouds and on the ground. These charges try to balance themselves by moving through the air, which we see as lightning. Lightning is a huge electrical current that travels through a narrow path of air very quickly, heating the air around it almost instantly.
When the air heats up, its pressure increases, causing it to expand rapidly. This expansion creates a shockwave, which is the thunderclap we hear. It’s a sudden and loud sound that contains a wide range of frequencies. This is similar to other loud noises, like the bang of a supersonic jet or the crack of a whip, because they all involve a quick burst of pressure.
As the shockwave from the thunder travels through the air, it loses energy. The higher frequencies of the sound fade away faster than the lower ones. So, if you are far from the lightning, the thunder sounds less sharp and more like a deep “boom.” The sound waves from different parts of the lightning bolt can also overlap and bounce off objects like trees, hills, and clouds, creating longer and lower-pitched rumbles.
Sometimes, lightning occurs entirely within a cloud. In this case, the sound waves start far away and get mixed up, so you might only hear a soft rolling sound or nothing at all.
In a single storm, many different lightning bolts create many different pressure waves. These waves reach your ears at different times, so you hear a mix of claps, booms, rumbles, and rolls. It’s like a natural symphony that has inspired many stories and legends over time.
Understanding thunder can be fascinating, and if you’re curious about the world around you, there are many resources to explore. For example, CuriosityStream offers a variety of shows about science, history, and more. You can learn about unusual natural events and other interesting topics.
Use simple materials like a flashlight, a metal sheet, and a balloon to simulate a thunderstorm. Inflate the balloon and rub it on your hair to create static electricity, then use the flashlight to mimic lightning. Finally, shake the metal sheet to produce thunder sounds. This will help you understand how lightning and thunder are connected.
Conduct an experiment to explore how sound waves travel. Use a slinky to demonstrate how sound waves move through the air. Stretch the slinky and create waves by pushing and pulling it. Observe how the waves change as they travel further, similar to how thunder sounds different based on distance.
Listen to recordings of different thunder sounds and map them based on their characteristics. Create a chart that categorizes the sounds into sharp claps, deep booms, and rolling rumbles. This activity will help you identify how distance and environment affect the sound of thunder.
Watch a video of a thunderstorm and create a timeline of lightning strikes and corresponding thunder sounds. Note the time difference between seeing the lightning and hearing the thunder to calculate the distance of the storm. This will reinforce your understanding of how light and sound travel at different speeds.
Write a short story or create a comic strip about a thunderstorm from the perspective of a character experiencing it. Include scientific explanations for the sounds they hear and the sights they see. This creative activity will help you apply your knowledge of thunder in a fun and imaginative way.
Here’s a sanitized version of the YouTube transcript:
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Thunder. We’ve always been fascinated by it, but for a long time, we weren’t sure what it was: the violent tantrum of a young god, the rumbling wheels of Thor’s chariot, or the flapping of a giant bird. It wasn’t until we understood the science of storms and sounds that we figured out what thunder is and why it sounds the way it does.
Storms have a lot going on, and we’ll take a rain check on explaining most of it. The key, as far as thunder goes, is that during a storm, positively and negatively charged particles build up in different places and then zig-zag through the air to get rebalanced. During this rebalancing, which we know as lightning, a giant electrical current rushes through a tiny channel of air in a fraction of a second, instantaneously superheating the surrounding air.
Since increasing the air’s temperature also increases its pressure, that air gets super-pressurized, causing it to explode outward in what we call a shockwave. This sudden explosion is what we experience when we hear a thunderclap; it’s a distinct sound that seems to come out of nowhere and contains an incredible range of frequencies. Those same qualities are actually common to any abrupt and intense burst of pressure, from the bang of a supersonic jet to the crack of a whip to the pop of a balloon to the snap of a tiny bolt of static electricity; that’s why all shockwaves sound surprisingly similar, at least if you’re nearby.
As a shockwave travels through the air, it loses energy, and that intense burst of pressure smooths out. The wave’s higher frequencies dissipate more quickly than its lower frequencies. So the farther away you are from lightning, the less sudden the onset of the sound is, and the lower the sound appears – instead of a sharp “clap,” you might hear a resonant “boom.” Waves from more distant parts of the lightning bolt take even longer to reach you and can overlap and echo off trees, hills, and clouds along the way, so you’ll hear them as longer, even lower-pitched rumbles. When lightning happens completely within a cloud, the waves start so far away and get so jumbled up that all you might hear is a soft rolling sound, or nothing at all.
Within a single storm, lots of waves of pressure from lots of different parts of lots of different lightning bolts intermingle and reach your ears at different times, so you’ll often hear a symphony of claps, booms, rumbles, rolls, and more. It’s a perfect storm of sound that has inspired countless stories.
I started working on this video because during a summer storm, it suddenly struck me that, despite knowing a thing or two about science, I had no idea what thunder actually was. If you have that same curiosity about the world around you, you’ll love CuriosityStream, the sponsor of this video, which has tons of expertly curated shows about science, history, food, travel, and more, for just $19.99 a year – less if you use our special promo code!
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This version maintains the original content while removing any informal or potentially inappropriate language.
Thunder – The sound that follows a flash of lightning, caused by the rapid expansion of air heated by the lightning. – Example sentence: During the storm, the loud thunder echoed across the sky after each flash of lightning.
Lightning – A natural electrical discharge of very short duration and high voltage between a cloud and the ground or within a cloud. – Example sentence: We saw a bright flash of lightning before we heard the rumble of thunder.
Sound – A form of energy that is produced by vibrating objects and travels through a medium such as air, water, or solids. – Example sentence: The sound of the bell ringing traveled through the air and reached our ears.
Waves – Disturbances that transfer energy from one place to another, often through a medium such as air or water. – Example sentence: Ocean waves carry energy across the surface of the sea, moving water and anything floating on it.
Pressure – The force exerted on a surface per unit area. – Example sentence: The pressure inside a balloon increases as more air is pumped into it.
Frequencies – The number of times a wave repeats in a given period of time, usually measured in hertz (Hz). – Example sentence: Different musical notes have different frequencies, which is why they sound different to our ears.
Storm – A violent disturbance in the atmosphere, often accompanied by rain, thunder, lightning, or snow. – Example sentence: The approaching storm brought heavy rain and strong winds to the area.
Particles – Small portions of matter, such as atoms or molecules, that make up substances. – Example sentence: In a gas, particles move freely and are spread far apart compared to those in a solid.
Energy – The ability to do work or cause change, existing in various forms such as kinetic, potential, thermal, and electrical. – Example sentence: Solar panels convert sunlight into electrical energy to power homes and devices.
Expansion – The increase in volume of a substance due to heating or other factors. – Example sentence: The expansion of the metal bridge in the heat of the day caused it to lengthen slightly.
