| Exam Board | Pre-U |
|---|---|
| Module | Pre-U 9794/2 (Pre-U Mathematics Paper 2) |
| Year | 2013 |
| Session | November |
| Topic | Radians, Arc Length and Sector Area |
| Type | Sector perimeter calculation |
| Difficulty | Moderate -0.8 This is a straightforward application of standard radian conversion and sector formulas with no problem-solving required. All three parts involve direct substitution into memorized formulas: converting degrees to radians (100π/180), perimeter = 2r + rθ, and area = ½r²θ. The calculations are routine with clearly given values. |
| Spec | 1.05d Radians: arc length s=r*theta and sector area A=1/2 r^2 theta |
1 The diagram shows a sector $O A B$ of a circle with centre $O$ and radius 9 cm . The angle $A O B$ is $100 ^ { \circ }$.\\
(i) Express $100 ^ { \circ }$ in radians, giving your answer in exact form.\\
(ii) Find the perimeter of the sector $O A B$.\\
(iii) Find the area of the sector $O A B$.
\hfill \mbox{\textit{Pre-U Pre-U 9794/2 2013 Q1}}