Dimensions of a Circle
Derive the formulae for the circumference and area of a circle using multiple representations.
Publisher: Texas Instruments UK
Editor: Barrie Galpin
Author: Allan Duncan
Topic: Mathematik
The tns file allows students to change the size of a circle and "capture" the length of its radius, diameter, circumference and area.
These data are stored automatically in a spreadsheet (page 1.4) and graphs can be drawn and analysed using pages 1.5 to 1.7. The dimensions of the circle are therefore represented in three ways: using geometry, as data in a spreadsheet, and in graphical format.
A lesson using this activity is described by Allan Duncan in a booklet entitled Inspired Connections in Maths Lessons. This description makes clear the power of the dynamically linked multiple representations to enhance student understanding.For a pdf version of the entire booklet please click here.
Notes:
a) On page 1.4, to clear the data collected, use
<3>< 4>
b) To redraw the graphs with axes appropriate for the data use the Zoom - Data command:
<5>< 2>
