The Secret Behind The Definition Of Air Pressure For Kids!

Joan Agie
Oct 19, 2023 By Joan Agie
Originally Published on Dec 03, 2021
Air pressure exists around the Earth because of air molecules

Also recognized as atmospheric pressure, air pressure is an invisible force.

Air pressure exists around the Earth because of air molecules pressing against surfaces. This cannot be seen, but we feel it during every moment of the day.

The atmosphere also has weight, even though it may not feel like it. It is so heavy that it pins the whole world down to the surface and holds it there.

It is a push that works from opposite directions but with the same purpose as gravitational pull. It helps to keep life on the surface of the Earth.

Not all regions on the Earth have equal pressure of air; it varies in different places, like on land and in the ocean, depending upon several factors. Atmospheric pressure is key to predicting and understanding the weather.

Air pressure is a body that is inversely parallel to altitude. When the altitude is low, say like that at sea level, the air will be under high pressure.

On the other hand, in the case of mountains that touch the clouds, the altitude is quite high, and as a result, atmospheric force decreases. Temperature is also a factor that determines whether there is less or more pressure in a region.

Areas with cold temperatures experience less air pressure. The temperature of the atmosphere coordinates directly with air pressure by increasing and decreasing with it. Hot regions with high temperatures experience high atmospheric pressure, as the air molecules there are a lot denser.

Lastly, moisture is also an indicator of atmospheric pressure. With a rise in humidity, air pressure falls, and the opposite happens when there is a decrease in the water vapor that stems from humidity.

It is possible to measure atmospheric pressure through an instrument called the barometer, which is a device invented by scientists. According to science, this device works through the process of measuring the degree of air pressure.

The oldest ancestor of this device is the mercury barometer, consisting of a mercury tube. The liquid mercury in this tube moves according to the atmospheric pressure in its surroundings, rising when the measure of this force is high and dropping when it is low.

This also indicates if the weather is too sunny or too cold. The unit used to measure air pressure is called atmosphere, and this unit is abbreviated to 'atm'.

Find out all there is to know about this invisible force and how it pushes down on Earth! If you like this article, why not check out other fun facts about the ocean and fishing?

What is air pressure's simple definition?

Air pressure can be referred to as atmospheric pressure.

The atmosphere is an invisible layer blanketing the Earth. However, this body is not as weightless as it may sound.

Air moves around us at all times. So, how do we not feel the weight of air?

Surprising as it may seem, air is constantly putting pressure on humans from all directions, forcing them to stay close to the Earth's surface and making it easier for gravitational pull to keep us rooted to the surface.

The process of air pressing down on us is a concept that is not as hard and technical to understand as it appears. Thus, atmospheric pressure is an external force concealed to the human eye, and the weight of this air keeps life on the ground.

So, the next time you wonder what keeps you in such close contact with the surface, you know that it is the force exerted by the weight of the atmosphere and not just the pull of gravity.

Why is air pressure so important to understand?

To understand the weather and even predict oxygen levels in a region, you must understand air pressure.

Air molecules have mass. Therefore, air is a weighty element and is very important. If we can figure out the puzzle that is atmospheric pressure, we will have pretty much cracked the code to predict or identify weather conditions in a particular place.

There are two kinds of atmospheric pressure: low pressure and high pressure. These vary depending upon the altitude, temperature, and humidity level of a place.

Weather patterns are not the same in every area. Where there is high barometric pressure, the weather is warm. While measuring air pressure in stormy weather conditions, a barometer records low air pressure.

Low pressure occurs when there is a lesser weight of air. In the case of rain, low pressure remains.

An ocean is close to the surface of the Earth, meaning that, because of the low altitude or sea level, there is high pressure. In cases involving a tall mountain, say the mighty Mount Everest, the altitude is at its peak, resulting in fallen air pressure. Therefore, the weather largely depends upon atmospheric pressure.

A life-saving fact is that the oxygen level drops gradually with an increase in altitude. This explains why mountain climbers have to carry artificial oxygen while climbing high peaks.

How can kids understand air pressure?

It is often the case that children understand concepts better when they can see a demonstration. Fortunately, many easy experiments can be conducted with items that are generally available at home!

Whenever you drink from a juice box, the only open space on it is the little gap through which you put the straw. There has to be at least one time when you have blown into the straw to hear the sound of bubbles gurgling inside.

What is notable here is that the juice climbs up the straw and escapes the unsealed end once you are done blowing into it. Why does this happen?

Air pressure plays a vital role in why this is happening. This can be demonstrated through an experiment involving a water bottle and a straw.

The straw must be dipped in a bottle filled halfway with water. The opening of the bottle around the straw is to be sealed with clay.

After making sure that the bottle is sealed properly, blow air into the straw, this leads to a rise in the air pressure inside the bottle. Consequently, this heightened air pressure inside the bottle forces the water inside the bottle to travel up and out of the straw.

Another experiment involves an empty glass filled with water to the top, even if it means spilling some of it over the rim. Then, use an index card instead of a lid, and place it firmly on top of the glass. Press down on it if needed.

The last step is to lift the glass and flip it around. Do not worry; there will be no spilled water to panic about.

Why? Because the water will remain inside the glass, as the air exerts a force against the lid from the outside. This push proves to be stronger than the gravitational pull, leading to unspilled water!

Books Kids Can Read To Learn About Air Pressure

Science is a fascinating world of its own. From units like a square meter to instruments like the barometer, science has offered the world several ways to understand itself.

The science of air pressure is intriguing; we get to discover what keeps us on the surface of our planet and even manipulates the weather.

There are many books to help your kids learn about air pressure. 'Wind and Air Pressure', written by Alan Rogers and Angella Streluk, introduces the idea of what air pressure is and explains all there is to know about how it is measured, why it exists, and the effects it can have.

'Air Pressure Driving The Kids', a work by Joanne Randolph, takes the readers on a tour to study the types of air pressures, where they exist, and why they exist.

Here at Kidadl, we have carefully created lots of interesting family-friendly facts for everyone to enjoy! If you liked reading about the definition of air pressure, then why not take a look at our articles on static electricity for kids or shape poems for kids.

We Want Your Photos!
We Want Your Photos!

We Want Your Photos!

Do you have a photo you are happy to share that would improve this article?
Email your photos

More for You

See All

Written by Joan Agie

Bachelor of Science specializing in Human Anatomy

Joan Agie picture

Joan AgieBachelor of Science specializing in Human Anatomy

With 3+ years of research and content writing experience across several niches, especially on education, technology, and business topics. Joan holds a Bachelor’s degree in Human Anatomy from the Federal University of Technology, Akure, Nigeria, and has worked as a researcher and writer for organizations across Nigeria, the US, the UK, and Germany. Joan enjoys meditation, watching movies, and learning new languages in her free time.

Read full bio >