Lesson 8

• Nask
• Middelbare school
• havo, vwo
• Leerjaar 2

Pressure in gasses

This lesson

• Recap
  
• Pressure in gasses
  

Recap

Pressure in liquids — Hydraulics

0.01 m2

0.4 m2

20 N

1

2

800 N

What do we know about this system?

• Fluids are incompressible

P​1​​=P​2​​

1

2

​A​1​​​​F​1​​​​=​A​2​​​​F​2​​​​

P​1​​=P​2​​

​A​1​​​​F​1​​​​=​A​2​​​​F​2​​​​

Rearranging the formula!

1

2

Write out in words what each symbol stands for

F​1​​⋅A​2​​=A​1​​⋅F​2​​

Worksheet hydraulics

Pressure in gasses

Pressure in gasses — Questions

1. What produces pressure in gasses?

2. Why does the pressure inside of a balloon increase when you put more air into it?

3. What is the relationship between the pressure in a gas and the volume of the container it is in?

4. Is the relationship between the pressure in a gas and the volume of the container it is in directly proportional and inversely proportional?

5. What do you call the pressure the air around you exerts on your body?

6. Is the pressure at a mountain top larger or smaller than at sea level? Explain why.

7. Why do mountain climbers have to carry oxygen tanks with them when climbing high mountains?

Link

Pressure in gasses — Questions

1. What produces pressure in gasses?

• The collisions between the particles in the gas
• The particles bumping into each other and their environment. 
  

2. Why does the pressure inside of a balloon increase when you put more air into it?

• The particles get pushed closer together. Because of this there are more collisions. This causes the pressure to rise.

Link

Pressure in gasses — Questions

3. What is the relationship between the pressure in a gas and the volume of the container it is in?

• Increasing the volume of the container causes the pressure to decrease.
• Decreasing the volume of the container causes the pressure to increase.

4. Is the relationship between the pressure in a gas and the volume of the container it is in directly proportional and inversely proportional?

•  It is an inversely proportional relationship

Link

Pressure in gasses — Questions

5. What do you call the pressure the air around you exerts on your body?

• Atmospheric pressure.

6. Is the pressure at a mountain top larger or smaller than at sea level? Explain why.

• At a mountain top the pressure in the air is smaller.
• This is because gravity's pull is weaker at that height.

7. Why do mountain climbers have to carry oxygen tanks with them when climbing high mountains?

• Because the air is less dense at great heights, because of this there is less oxygen in the air.

Link

Homework

• Look at the following Phet simulation — What can you learn about pressure in gasses about it?
  

• Do the ybellowblock exercises of 8.5 and 8.5.