The Science of Sound

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Sound is an incredible feature in the world around us. But what exactly is sound? How do our ears experience it?
Sound is the energy produced by things when they vibrate. When someone bangs a drum, the tight skin vibrates at a high speed when hit, forcing the air around it to vibrate as well. As the air moves, energy travels out of the drum in every direction. The air inside of your ear eventually vibrates, and thus you perceive the drum’s vibration as sound.

Basically, there are two different aspects involved with sound. First, there is the physical process that produces sound and sends it into the air (like the vibrating drum). The second process is separate and psychological, occurring inside of our ears and brain, converting the incoming sound energy into the interpreted noises we recognize.

The brilliant English scientist known as Robert Boyle (1627–1691) was the first person to discover that sound needs a medium to travel through. He conducted an experiment where he placed an alarm clock inside of a large glass jar, and made it ring. As it rang, Boyle sucked all the air out of the pump. As the air disappeared, the sound died out because it had nothing to travel through. This was a groundbreaking discovery in the world of science.

Sound works in a similar way to light, where it travels outward from a definite source, the same way light travels from the Sun or a lightbulb. There are also some vast differences between the two as well. For instance, we know light can travel through a vacuum, otherwise Earth would be a very dark place. Sound however, cannot travel in a vacuum, and many of the science fiction movies you watch where a spaceship or object explodes, would in reality be completely silent.

The way sound travels is incredible. When you hear an alarm clock ringing, what you are perceiving is energy making a journey. From inside the clock, the sound originates. It travels through the air, arriving in your ears. The process is similar to how waves travel over the ocean.

Sound also has a speed limit. It can only move the air in its energy pattern between two places at a defined speed. When you hear someone say that a jet airplane has “broken the sound barrier”, it means that the physical plane itself is moving faster than it takes for it’s sound to reach your ears.
Sound is a fascinating scientific phenomenon. It keeps us alert and present in our lives. Make sure that you keep your hearing healthy by doing annual checkup with a hearing healthcare provider. Find a clinic near you!