Lightning | Electricity | Physics | FuseSchool

Summary

In 1752, Benjamin Franklin discovered that lightning is caused by electrical discharges in clouds. Lightning occurs when charged particles in storm clouds build up, creating an imbalance that seeks to resolve itself through a lightning bolt. This powerful discharge heats the surrounding air, causing the rumbling thunder. While lightning is a dangerous force, scientists are still exploring ways to harness its energy. However, the immense power and unpredictability make it difficult to store. Protective measures like metal frames in cars, buildings, and airplanes help shield us from lightning strikes.

Takeaways

• ⚡ Lightning is caused by powerful electrical discharges in clouds due to the separation of positive and negative charges.
• 🪁 Benjamin Franklin proved lightning is electrical by flying a kite during a thunderstorm, though he narrowly avoided being struck.
• ☁️ Thunderstorms form when water molecules in clouds move against each other, creating charged particles and two poles within the cloud.
• 🌩️ The electrical imbalance between storm clouds and the ground results in lightning bolts that can carry either positive or negative charges.
• 👀 The visible lightning bolt is an electrical arc created when an invisible lightning bolt approaches the ground and discharges energy.
• 🔥 Lightning heats surrounding air to temperatures five times hotter than the Sun, causing rapid air expansion that creates thunder.
• 🌈 Lightning can appear in different colors depending on humidity, temperature, and air pollution levels.
• 💡 Each lightning bolt carries about 10 billion watts of power—enough to supply electricity to 32 million people for a year.
• 💰 Harnessing lightning electricity is currently impractical due to unpredictability, immense energy levels, and exorbitant equipment costs estimated at $90 trillion USD.
• 🚗 Cars, houses, and airplanes are protected from lightning by metal frames, conducting rods, and rubber tires that safely direct the electrical charge to the ground.
• ☁️ Thunder is the sound created by the rapid expansion and vibration of air heated by the lightning bolt.

Q & A

What did Benjamin Franklin discover about lightning in 1752?

Benjamin Franklin discovered that lightning is caused by powerful electrical discharges in clouds. While he wasn't the first to think this, he proved it by flying a kite during a thunderstorm.

Why is it lucky that Benjamin Franklin’s kite wasn't struck by lightning?

It was lucky because if the kite had been struck by lightning, it would have fried Benjamin Franklin, potentially killing him due to the extreme electrical power.

What causes thunderstorms?

Thunderstorms are caused by small electrically charged particles in clouds, where water molecules are heated and cooled, causing them to move against each other. This creates an imbalance of charge, leading to lightning.

How does lightning form within a cloud?

Lightning forms when a separation of charge occurs in the cloud, with one part becoming negatively charged and the other positively charged. This imbalance of charges causes a current to pass between the differently charged poles.

Why does lightning sometimes have a positive charge and sometimes a negative charge?

The charge of lightning varies based on the specific conditions of the storm, such as the type of cloud and the relative positions of charged particles, leading to either positive or negative charges in the bolt.

How does lightning produce the rumbling sound we hear as thunder?

The lightning bolt heats the surrounding air to extreme temperatures, causing it to expand rapidly. This rapid expansion creates vibrations in the air, which result in the sound we hear as thunder.

What factors determine the color of a lightning bolt?

The color of lightning is influenced by atmospheric humidity, temperature, and air pollution levels. These factors affect how the lightning interacts with the air and the particles in it.

How much power does a single lightning bolt carry?

A single lightning bolt carries about 10 billion watts of electricity, which is enough power for approximately 32 million people for a year.

Why is harnessing lightning energy not practical at the moment?

Predicting where lightning will strike and capturing its energy is difficult because the charge can be either positive or negative. Additionally, developing technology to store such a massive, instantaneous amount of power would be incredibly expensive and complex.

How are we protected from lightning in cars, houses, and airplanes?

Cars are protected by their metal frames and rubber tires, which conduct the electrical charge safely to the ground. Houses and buildings use conducting rods to channel the lightning safely. Airplanes are protected by their metal shell, which allows the lightning to travel through it without harming passengers.