# Virtual Car Homework #4

 This is an individual assignment. You are encouraged to discuss the question as a team, but be sure to write the answers in your own words.

# Distance

One of the things that Virtual Car does is predict the distance that your car can travel.

In order to calculate this, Virtual Car uses an equation that includes the following things:

• Length of the spring
• Thickness of the spring material
• Diameter of the axle that the spring is wrapped around
• The inner diameter of the spring case
• The diameter of the drive wheels.
Describe, in conceptual terms, how you think the "distance the car can travel" depends on these things. If you can think of any equations, write them down. At minimum, you should describe in your own words how you think each thing affects the distance that the car will travel. You may include hand-drawn sketches if it helps you explain it.

Hint: the distance the car can travel is the number of revolutions it takes to wind the spring all the way, multiplied by the distance the car travels with each revolution. Predicting the "number of revolutions" calls for a pretty complicated equation (you would need calculus to set it up), but "distance per revolution" has a pretty easy equation. Feel free to take a guess at either one.

## Grading

This memo will be graded based on the thoughtfulness of your answers.