Answers to Questions about Coordinate Systems

The following answers are brief and intended as guidelines only. Student answers may vary with the sources they use.

1.  What did a housefly have to do with Descartes’s coordinate system?

ANS: It inspired its creation. He was watching a fly on a tile ceiling and realized he could indicate the fly’s location by counting the tiles.

2.   What did Descartes fail to do that caused him to publish hypotheses that included errors?

ANS: He failed to perform experiments to prove his ideas.

3.   What is the shape of the work area required by a robot with a Cartesian configuration?

ANS: A robot with a Cartesian configuration moves within a rectangular space—up, down, back and forth, and from side to side.

4.   Geographic coordinates give the ability to locate points on the earth. At what longitude is the prime meridian located?

ANS: Zero degrees longitude.

5.   Why would mapping the surface of the earth be more difficult than mapping the surface of an equally large billiard ball?

ANS: The earth’s surface is uneven, so coordinates must factor height and/or depth.

6.   Which coordinate system is used by astronomers to locate objects in outer space?

ANS: Polar or spherical.