This activity continues our exploration of circle measurements. You will need to read the directions and answer the questions found in your packet.

1.) Slowly move the "Change Angle" slider all of the way to the right until entire circumference has been traced. How many arc lengths are formed? Are all arc lengths equal? Why not?
2.) Next, you will measure each central angle. Select the "angle" tool in the upper left-hand corner.
-Select any of the points constructed on the circle.
-Select the center point.
-Select a consecutive point constructed on the circle.
-Pull the angle measurement out from the center of the circle so you can see it better if necessary
-Repeat for each angle
3.) What is the sum of the measures of the angles in the circle? What did you expect the sum to be?
Why is there a difference?
4.) Check out the definition of a "radian"
5.) How many degrees are in 1 radian? How many radians are in 1 degree?
6.) How many radians are in a circle? (HINT: Use your previous answers)
7.) How many radians are in a semicircle?
8.) What is the significance of the answer to question 7?