Measuring Gas Pressure and Atmospheric Pressure

TL;DR

This video explains atmospheric pressure, how it is measured, and the use of manometers and barometers in measuring pressure.

Transcript

did you know that the air all around us pushes on us pushes on things it's called atmospheric pressure sometimes referred to as barometric pressure we're going to learn about that in this video we're also going to learn about how we can measure the pressure of both the gas in the atmosphere and also just like the amount of pressure that's in say li... Read More

Key Insights

• 🤙 Atmospheric pressure, also called barometric pressure, is the force exerted by the air around us.
• 🫢 Gas pressure is a result of the constant motion and collisions of gas particles.
• 🫢 Manometers are used to measure gas pressure in containers, while barometers measure atmospheric pressure.
• 🫢 Measuring pressure using a U-tube with a vacuum helps isolate the pressure from the gas sample or the atmosphere.
• ❓ Atmospheric pressure decreases as altitude increases and increases as altitude decreases.
• ❓ Mercury is commonly used in manometers because of its density, stability, and accuracy in pressure measurements.
• 💦 Different units, such as millimeters of mercury and millimeters of water, can be used to measure pressure.

Questions & Answers

Q: What is atmospheric pressure and how does it affect us?

Atmospheric pressure, also known as barometric pressure, is the force exerted by the air around us. It pushes on everything, including our bodies, but since it pushes on all parts of us equally, we do not feel it. It is highest at sea level and decreases as altitude increases.

Q: How do manometers measure pressure in gas tanks?

Manometers are used to measure the pressure of gas samples in containers. One end of the U-tube is attached to the gas tank, and the other end is sealed. The gas pressure pushes down on one side of the U-tube, causing the liquid (usually mercury) to rise on the other side. The height difference is measured to determine the pressure.

Q: Why is mercury commonly used in manometers?

Mercury is used in manometers because it is a liquid metal that is denser than water. Its density helps provide accurate pressure measurements due to its weight and stability.

Q: How does altitude affect atmospheric pressure?

As altitude increases, the amount of air above decreases, resulting in lower atmospheric pressure. This is because there are fewer air particles pressing down from above. Conversely, going below sea level, where there is more air above, increases atmospheric pressure.

Summary & Key Takeaways

• The video explains that the air around us exerts pressure, known as atmospheric pressure or barometric pressure.

• Gases exert pressure by the constant motion and collisions of their particles, which keeps objects like tires or balloons inflated.

• Two methods of measuring pressure are discussed: using a U-tube with a vacuum for atmospheric pressure, and using manometers for gas pressure in containers.