Name:____________________________________
Date:___________________
3A 4A 3B 4B
Today we are going to calculate the distance we can expect our dragsters to travel. There are several
things we will need to know in order to make this calculation. First, we need to know what resources we
will have. Then we will need to calculate the relevant sizes and lengths of our materials. Lastly, we will
need to use these numbers in appropriate computations to arrive at a good answer.
Our Resources:
2 CDs for back wheels.
Diameter = 4 ¾ inches or 121 cm
A 3 inch long dowel rod
Diameter = ¼ inch
A mouse trap
A lever arm
12 inches long
CALCULATIONS:
To get to the point where we can calculate the distance that the car will travel, we will need to establish
how far it will travel every time the wheel turns, then multiply that by the number of times we can
expect it to turn.
1. What is the circumference of the back wheel? The formula for circumference is pi x diameter.
Write down the math sentence that you would need to follow and give the solution:
2. What is the circumference of the axel (the ¼ inch dowel)? The formula for circumference is
pi x diameter. Write down the math sentence that you would need to follow and give the
solution:
3. Now we need to figure out the maximum length of a string that could be tied to the lever arm
and connected to the axle. Illustrate how far the 10 inch lever arm could travel and then make
an educated guess how long the string that connects the lever to the axle could be.
Use the information you calculated on the front of this paper to fill in the following statements.
4. The wheel will travel _______________ inches every time the axle rotates.
5. The axle has a circumference of _______________ inches.
6. The maximum length of the string is ________________ inches.
7. Calculate the total number of revolutions the axle will make, if the string’s length is wrapped
around it. The axle will turn ______________ times.
8. Calculate the total distance the back wheel will travel, given the number of axle rotations. The
wheel will travel ______________ inches.
9. Convert the number of inches the wheel will travel into an equal value of Feet and inches. The
wheel will travel ___________ feet and ______________ inches.