Soc 20- Levers

Question 1

What does the term lever refer to in the context of the body?

Answer 1

A system of muscles and bones working together to bring about a movement

This involves muscles pulling on bones to create movement.

Question 2

What are the four components of a lever?

Answer 2

• Fulcrum
• Load
• Effort
• Lever arm

These components work together to facilitate movement.

Question 3

What is a fulcrum in a lever system?

Answer 3

The point around which the lever rotates (joints)

The fulcrum serves as the pivot point for the lever.

Question 4

What does the load refer to in a lever system?

Answer 4

The force that is applied by the lever system (resistance/object)

This is the weight or resistance that the lever must overcome.

Question 5

What is meant by effort in the context of a lever?

Answer 5

A force that is applied by the user of the lever system (muscles)

This is the force exerted by muscles to move the load.

Question 6

What is a lever arm?

Answer 6

A rigid bar such as a bone

The lever arm transmits the force from the effort to the load.

Question 7

How are levers classified?

Answer 7

According to the placement of the fulcrum, load, and effort

The classification affects how the lever operates.

Question 8

What are the three classes of levers?

Answer 8

• First class
• Second class
• Third class

Each class has a different arrangement of the fulcrum, load, and effort.

Question 9

1 Example of a first class lever

Answer 9

Example 1: Tricep dip.
The elbow is the fulcrum which sits between the load (bodyweight) and the effort applied by the tricep.

Question 10

Example of a second class lever

Answer 10

Example 2: Lifting a wheelbarrow
The weight on the wheelbarrow you’re carrying is the load, which sits between the wheel (fulcrum) and the handle (effort).

Question 11

Example lf a 3rd class lever

Answer 11

Example 2: Using a spade
The effort is applied by the foot (gastrocnemius), which is between the fulcrum at the handle and the weight of the soil (load).