Station 3: The Friction Factor Experiment
Objective
To observe how wheels and axles reduce friction to make moving objects easier.
Materials Needed
One heavy textbook
Two round pencils or dowels
Part A: Identifying Parts
Look at the diagram of the wagon:
Label the components: Identify which part is the wheel and which part is the axle.
Wheel: The large round part that touches the ground.
Axle: The rod that goes through the center of the round part.
Step-by-Step Instructions
The Drag Test:
Place the heavy book flat on the desk.
Use one finger to push the book slowly across the surface.
Observation: Notice how much effort it takes to get it moving.
The Roller Test:
Place the two round pencils parallel to each other on the desk.
Set the heavy book on top of the pencils.
The Move:
Use one finger to push the book again.
Observation: The pencils should roll underneath the book.
Observe:
Pay attention to the difference in how much force (pushing power) you need to apply between the two tests.
Data Table: Comparing Force
Method of Moving
Dragging the book flat
Rolling the book on pencils
Force Needed (Evaluate as High, Medium, or Low)
Part B: Real-World Application
Observation: What did you feel change when you added the pencils?
Concept: Think about the simple machines studied today.
Question: Explain one way a wheel and axle helps us complete a task in our daily lives.
Example: A wheel and axle helps us by enabling easier movement of heavy objects, such as moving furniture or vehicles.
Understanding Wheel and Axle
Description
A wheel and axle is a simple machine made of two circular objects of different sizes:
Wheel: The larger circular object.
Axle: The smaller rod in the center.
They are locked together, such that when one rotates, the other must also rotate.
Functionality
In this machine, the center of the axle acts as the fulcrum (the pivot point).
Due to the wheel being much larger than the axle:
You can move the outer edge of the wheel a long distance with relatively less force.
Mechanical Advantage
Why do we use this machine?
It provides us with Mechanical Advantage.
This term refers to the capability of a machine to amplify an input force.
Example of Application: A wheel provides a thick handle (the wheel) that makes it easier to twist a stubborn screw into hardwood due to the leverage gained from the larger wheel compared to the axle (the metal tip).