# What is Air Pressure? | Don't Memorise | Summary and Q&A

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July 3, 2019
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Infinity Learn NEET
What is Air Pressure? | Don't Memorise

## TL;DR

Air exerts pressure in all directions and its weight varies in different layers of the atmosphere.

## Key Insights

• π» Air exerts pressure in all directions, allowing objects like a piece of cardboard to stick to a surface.
• π The atmosphere is the envelope of air surrounding the Earth, divided into layers.
• π± The bottom layer of the atmosphere carries the maximum air pressure.
• π± Air pressure decreases as altitude increases.
• π¨ Moving air is called wind.
• π¨ The speed of the wind affects air pressure.
• π± The weight and pressure of air vary in different layers of the atmosphere.

## Transcript

Look at this glass! What do you see inside it? Many of you would probably say that itβs empty! However itβs not. Then whatβs inside it? There is AIR inside this glass! Yes, air is present everywhere around us. But tell me, is air heavy? We generally feel that air is light in weight. How true is this? Let us do an experiment to see how heavy the air... Read More

### Q: Why does the cardboard stick to the bottle's surface when the bottle is inverted?

The air's pressure pushes the piece of cardboard upward, causing it to stick to the surface. Air pressure acts in all directions, allowing it to exert force on objects.

### Q: What is the envelope of air surrounding the Earth called?

The envelope of air is called the atmosphere and is divided into different layers, including the troposphere, stratosphere, and mesosphere.

### Q: Is air pressure uniform throughout the layers of the atmosphere?

No, as we move higher in the atmosphere, the quantity of air decreases, resulting in lower air pressure. The bottommost layer carries the maximum air pressure.

### Q: What happens to air pressure when wind speed increases?

When wind speed increases, the air pressure decreases. Stronger winds create a lower atmospheric pressure in the surrounding area.

## Summary & Key Takeaways

• The experiment with a cardboard and water-filled bottle demonstrates that air exerts pressure, allowing the cardboard to stick to the bottle's surface.

• The atmosphere is the envelope of air surrounding the Earth, divided into different layers.

• The bottom layer carries the maximum air pressure, while pressure decreases as we move higher.