Property of Circles
Purpose: The goal of this lab is to practice graphing and graphical analysis. You will also determine a relationship between the circumference and the diameter of a circle.
Procedure:
2. For each object: (i) Measure the circumference (C) by wrapping a thread around the circular section and finding the length of the thread. (ii) Measure the diameter (D) of the corresponding circular cross section. Record your data in an appropriate table.
3. Prepare a sheet of graph paper for plotting C versus D. You should make "C" the vertical axis and "D" the horizontal axis. Each axis should be given a uniform scale. Each axis should be labeled and appropriate units indicated. The graph should have a title.
4. Plot your data on the graph.
5. Draw a "best fit" line to the points on your graph.
6. Determine the slope of your line.
7. Interpret the value of the slope that you obtained. What does the slope tell you about the relationship between C and D?
8. Application:
The Earth is approximately a large sphere. The Earth has a radius of
6.378 x 10+3 km and
an equatorial circumference of 4.007 x 10+4
km. Imagine that you wrapped a belt snugly around the equator. It would
have a length of 4.007 x 10+4 km. Now imagine
that you wanted to add some material to the belt so that when it encircled
the Earth it would be everywhere 2 m above the surface.
How much additional material would you have to add?