Lesson 3

Wheel IconThe Wheel & The Ramp icon Axle


Graphing - 2::

To look at the relationship between wheel radius and effort force, use the data from Table 2 to complete Graph 2A in your lab packet.

Analysis Questions:

  1. What happens to the effort force as the radius increases? Use complete sentences to record your answer in your lab packet.
  2. Do your results match your predictions? Record a comparison between your predictions and your results in your lab packet.

Let's take a closer look at this wheel and the attached screw (axle) to get a better understanding of what is happening.

Content on this page requires a newer version of Adobe Flash Player.

Get Adobe Flash player

We can think of the wheel and axle as a specialized lever.
Click on the wheel to see this relationship.

3. Recall from the lever activity that as the length of the effort arm of a lever is increased, the effort force needed is reduced. If an increase in the length of an effort arm result in a decrease of effort force, explain why an increase in the radius of a wheel results in a decrease in effort force needed.

4. As the radius of the wheel increases, what happens to it's circumference?

5. How does this change the distance the handle moves to make one full rotation?

6. What would you gain if you applied the effort force at the axle instead of at the outside of the wheel?

reminder: Fe X De = Fr X Dr