1. Measurement
in a circle.
Spider & web, Ugley Green, Essex by flickr user hungrybrowser

4. 1 RADIAN
When the arc of a
circle has the same
length as the radius
the measure of the
angle is 1 radian.

5. CONVERTING DEGREES AND RADIANS
D R
=
180° π
D is an angle in degrees R is an angle in radians

6. Convert 20° into radians.

7. Convert 25° into radians.

8. Convert radians into degrees.

9. A bicycle wheel has a diameter of 0.4 meters. A point on the outer
rim travelled 2.6 m. How many degrees has the wheel turned?

11. Exercise #1
Questions: 1 ­ 8, 11, 12 and 13

12. Attachments
2879853255_b8754a23dc.webloc