What is air pressure?

Air pressure is the force that the air around us exerts on everything it touches.

It's like the weight of the air, pushing down on us.

We can't see air pressure, but we can feel it. For example, when you blow up a balloon, you're increasing the air pressure inside the balloon. This makes the balloon expand because the air is pushing against the inside of the balloon.

Air pressure is also what makes airplanes fly. Airplanes have wings that are shaped so that the air pressure is lower on top of the wing than it is on the bottom. This difference in air pressure creates lift, which is what keeps the airplane up in the air.

Air pressure changes with altitude. At higher altitudes, there is less air, so the air pressure is lower. This is why it's harder to breathe at high altitudes.

Air pressure also changes with temperature. Warm air has lower air pressure than cold air. This is why you can sometimes see waves in a hot cup of coffee. The hot air rises, which creates lower air pressure, and the cooler air sinks, which creates higher air pressure.

Air pressure is an important part of our everyday lives. It helps us to breathe, it helps airplanes to fly, and it even affects the weather.