Thunder is the sound that accompanies lightning during a thunderstorm. Sounds simple enough, but why does lightning even make a sound?
Any sound you hear is made up of vibrations. The vibrations travel as a sound wave through the air, until they reach your ear. Lightning is a huge discharge of electricity, and this electricity shoots through the air, causing vibrations to be formed in two ways:
1. The electricity passes through the air and causes air particles to vibrate. The vibrations are heard as sound.2. The lightning is also very hot and heats up the air around it. Hot air expands, and in this case the air expands very quickly, pushing apart the air particles with force and creating more vibrations.
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