Lesson 13 2E

• Science
• Middelbare school
• havo
• Leerjaar 2

This lesson

• Two types of relationships
• Pressure in gasses (8.5)
• Pressure, volume and temperature (8.6)


• Phet simulation
• Working on exercises

Learning goals

By the end of this lesson you will be able to:

• Name two types of scientific relationships and to give an example for each.
• Explain why gasses exert a pressure on their surroundings.
• Describe the relationship between pressure, volume and temperature in gasses.
• Explain what is meant by atmospheric pressure.

Two types of relationships

Directly proportional

Inversely proportional 

Example:

The relationship between weight on a spring and it's extension.

Example:

The relationship between weight on a spring and it's extension.

Directly proportional?

Inversely proportional?

Directly proportional:

When one factor increases, the other one also increases

Inversely proportional:

When one factor increases, the other one decreases

Directly proportional:

When one factor increases, the other one also increases

Inversely proportional:

When one factor increases, the other one decreases

Exercise:

come up with two examples for each type of relationship

Directly proportional:

• The time you exercise for and how much energy you use.
• The amount of hours you work and how much money you make.

Inversely proportional:

• The speed of a car and how long it's journey is.
  
• The amount of money you have and how much stuff you buy.
  

Exercise:

come up with two examples for each type of relationship

Pressure in gasses — Questions

1. What causes a gas to exert pressure on its surroundings?

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

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

4. Describe the relationship between the pressure in a gas and the temperature of the gas. What type of relationship is this?

5. What will happen to the tires of your bike on a hot summer day compared to a cold winter day? Assume the same amount of air is in them in both days.

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

7. Is the pressure at a mountain top larger or smaller than at sea level? Explain your answer.

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

Link

Learning goals

By the end of this lesson you will be able to:

• Name two types of scientific relationships and to give an example for each.
• Explain why gasses exert a pressure on their surroundings.
• Describe the relationship between pressure, volume and temperature in gasses.
• Explain what is meant by atmospheric pressure.