Lesson 2.4: More Levers

You have learned what first class levers look like. What are some examples of tools that you have around the house that use first class levers as the simple machine that makes them work?

Read First Class Levers around the House on page 136 in your textbook. Then, answer the following question.

Question 1. List the ten first class levers described in the reading.

 

Then, return here to continue this lesson.

 


The second type of lever is called a second class lever. Surprise, surprise! What is the difference between a first class lever and a second class lever?

Read Second Class Levers on page 136 in your textbook.

Question 2. What is the difference between a first class lever and a second class lever?

Question 3. Draw a diagram of a second class lever.

Question 4. Give four examples of second class levers used as tools are the home.

 

Then, return here to continue this lesson.

 


What do you think the name of the third type of lever is? Good guess! It is a third class lever. What is the difference between a third class lever and a first class lever or a second class lever? Was that a good guess, too?

Read Third Class Levers on page 137 in your textbook to make sure you guessed right.

Question 5. What makes a third class lever different from a first class or a second class lever?

Question 6. Draw a diagram of a third class lever.

Question 7. Give seven examples of third class levers used as tools.

Question 8. Which of the following are second class levers? Which are third class levers?

 

Then, return here to continue this lesson.

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 1. List the ten first class levers described in the reading.

The ten first class levers described in the reading are
- crowbar
- garden clippers
- hammer
- pliers
- tin snips
- scissors
- binder or clipboard
- light switches
- lawnmower speed controls
- hand brakes (Did you read about them in Try This?)

 

Click to return to where you left off in this lesson.

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 2. What is the difference between a first class lever and a second class lever?

The difference between a first class lever and a second class lever is that the load is between the effort and the fulcrum in a second class lever.

Question 3. Draw a diagram of a second class lever.
Your diagram must have the load between the effort and the fulcrum. Here is one example of a second class lever.

Question 4. Give four examples of second class levers used as tools around the home.

The four examples of second class levers used as tools around the home are a wheelbarrow, a can opener, a bottle opener, and a nutcracker.

 

Click to return to where you left off in this lesson.

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 5. What makes a third class lever different from a first class or a second class lever?


The effort is between the fulcrum and the load in a third class lever.

Question 6. Draw a diagram of a third class lever.

Your diagram must have the effort between the load and the fulcrum. Here is one example of a third class lever.

Question 7. Give seven examples of third class levers used as tools.

The seven examples of third class levers used as tools are fishing rod, axe, tennis racket, hockey stick, tongs, brooms, and tweezers.

Question 8. Which of the following are second class levers? Which are third class levers?

B is the only second class lever. The load is between the effort and the fulcrum.
C and D are third class levers. The effort is between the load and the fulcrum.

 


Click on the page forward to continue Lesson 2.