Why aren’t you crushed by air pressure?

This video shows how you can do the can crush experiment at home with a bunch of simple household items and at the end you will have violent can crush effect. This experiment helps the kids to understand the effect of atmospheric pressure on our body, and the need of spacesuit during a space travel.

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Well, you probably don’t think about air pressure all that much. But for a moment, let’s do just that. Humor me.

At sea level, because of the 60-mile column of atmosphere between you and outer space, there’s about 15 pounds per square inch of air pressure pushing down on every part of your body.

Now go pick up a 15-pound weight. Imagine if one of those were pressing down on your body, at all times, on every square inch.

At this point you might be wondering, “Why am I not being crushed at this very moment by air pressure?”

The answer is that there’s also air inside your body, pushing outward at the same pressure. So the forces acting on your body are equalized. Equilibrium is a great state. Almost as great as Texas.

This also helps explain why your ears pop when, say, you take the elevator to the 60th floor observation platform in Chase Tower. As you go up the air pressure around you is decreasing, but the air pressure inside your body is not decreasing as fast.

The “pop” you feel is simply the air inside your body rushing out to equalize with the ambient air pressure higher up.