Pascal (unit) facts for kids

Quick facts for kids Pascal
A pressure gauge reading in psi (red scale) and kPa (black scale)
General information
Unit system	SI unit
Unit of	Pressure or stress
Symbol	Pa
Named after	Blaise Pascal
Conversions
1 Pa in ...	... is equal to ...
SI base units:	kg⋅m−1⋅s−2
US customary units:	1.450 × 10−4 psi
atmosphere:	9.869 × 10−6 atm
bar:	10−5 bar

The pascal (symbol: Pa) is a special unit used to measure pressure or stress. It's part of the SI system, which is used by scientists and engineers worldwide.

Imagine pushing on something. Pressure is how much force you put on a certain area. So, one pascal is like one newton of force spread over one square meter.

You might see the pascal used in weather reports. There, it's often called a hectopascal (hPa). One hectopascal is 100 pascals. You might also see kilopascals (kPa) on things like bicycle tires. One kilopascal is 1,000 pascals.

To give you an idea, one hectopascal is about 0.1% of the normal air pressure at sea level. One kilopascal is about 1% of that same air pressure.

The pascal unit is named after a brilliant French mathematician and physicist named Blaise Pascal.

What is Pressure?

Pressure is a way to describe how much force is pushing on a surface. It's not just about how strong the push is. It also matters how big the area is where the force is applied.

Think about standing on snow. If you wear regular shoes, you might sink. This is because your weight (force) is on a small area. But if you wear snowshoes, your weight is spread over a much larger area. This means less pressure on the snow, so you don't sink!

How is Pressure Measured?

Pressure is measured by dividing the force by the area it pushes on.

• The force is measured in newtons (N).
• The area is measured in square meters (m²).

So, one pascal (Pa) is equal to one newton per square meter (N/m²). This simple formula helps us understand how pressure works in many different situations.

Blaise Pascal: The Man Behind the Unit

The pascal unit is named after Blaise Pascal (1623–1662). He was a very smart person from France. He made important discoveries in many areas.

Pascal was a mathematician, a physicist, an inventor, and even a writer. He did a lot of work on how fluids (liquids and gases) behave. He also studied pressure and how it changes.

Pascal's Principle

One of his most famous ideas is called Pascal's Principle. This principle explains that if you change the pressure in one part of a closed fluid, that change will be felt equally throughout the entire fluid.

This idea is super important for many technologies we use today. For example, it helps us understand how hydraulic brakes in cars work. It also explains how hydraulic lifts can raise very heavy objects using only a small force.

Pascal in Everyday Life

You might not realize it, but the pascal unit is used all around you.

Weather Reports

When you watch the weather forecast, you often hear about "barometric pressure." This is the pressure of the air around us. It's usually given in hectopascals (hPa). High pressure often means clear skies, while low pressure can mean storms.

Car and Bicycle Tires

When you inflate your car or bicycle tires, you add air pressure. This pressure is often measured in kilopascals (kPa). Having the correct tire pressure is important for safety and for how well your vehicle performs.

Diving and Water Pressure

When you dive deep into water, you feel the pressure increase. This is because the weight of the water above you pushes down. Scientists and divers use pascals to measure this water pressure. The deeper you go, the higher the pressure.

Other Units of Pressure

While the pascal is the official SI unit, other units are also used to measure pressure.

• Pounds per square inch (psi): This unit is common in the United States, especially for tire pressure and industrial uses.
• Atmosphere (atm): This unit represents the average air pressure at sea level.
• Bar (bar): This unit is very close to one atmosphere and is often used in meteorology and oceanography. One bar is equal to 100,000 pascals.

Understanding the pascal helps us make sense of many things in the world. From weather to how machines work, pressure is a key concept.

See also

In Spanish: Pascal (unidad) para niños