Geogebra - What Circumference does this circle have?

In this activity we will investigate the relationship between a circle and its diameter.

  1. Load this Geogebra file

You should see a circle.
  1.  Now move the point labelled "X"

You should see the circumference change.

  1. Use this spreadsheet to record the measurement of the circumference!
  

 

 
Questions
  1. What is the circumference measurement unit?
  2. What is radius of the circle if the diameter is 2 mm?  How did you work the answer?
  3. Does your spreadsheet data file reveal a relationship between the diameter and circumference measurement?
Activities
  1. Change the circle  shape by moving point X again.  Keep changing the diameter until you have filled your spreadsheet data table.
  2. Save a copy of your spreadsheet in your "Maths is Amazing" folder.