1. Starter The perimeter of this sector is (2r + 12∏) m. Find the radius r m, of the sector. r m

2. Arcs and Sectors Learning Objectives: Able to solve problems in terms of pi Able to calculate the arc length Able to calculate the area of a sector 11/09/2012Grade A/A*

3. Arc Length 30 o What fraction of the circle is shown by this sector? To calculate the length of an arc or area of a sector, we need to know this.

4. Arc Length An arc is a fraction of the circumference We get this fraction from the angle at the centre

5. Arc Length r

6. 30 o 18cm

7. Area of a Sector r

8. Area of sector 30 o 18cm

9. Arcs and Sectors Calculate the length of the arc and the area of the sector 70 o 11m

10. Starter Find the length of the arc and area of the sector Find the radius of this sector.

11. Arcs and Sectors Learning Objectives: Able to calculate the arc length Able to calculate the area of a sector Able to find the radius, given the arc length or area of a sector 11/09/2012Grade A/A*

12. Arcs and Sectors Find the radius of this sector. Give your answer to 1dp. (÷ ∏) (√)

13. Arcs and Sectors Calculate the angle at the centre of this sector. Give your answer to 1dp. (x 360)

14. Arcs and Sectors Calculate the angle at the centre of this sector. Give your answer to 1dp. (x 360) 125cm 2 9cm

15. Starter 27 o 256m 2 Calculate the length of the arc of the major sector.

16. Starter 27 o 256m 2 (÷ ∏) (√)

17. Starter 27 o 256m 2 9.386…m

18. 145 o 9cm

19. 16 o 14m 175cm 2 r 13cm