| Exam Board | WJEC |
|---|---|
| Module | Unit 3 (Unit 3) |
| Year | 2018 |
| Session | June |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Radians, Arc Length and Sector Area |
| Type | Arc length calculation |
| Difficulty | Moderate -0.8 This is a straightforward application of arc length and sector area formulas (s = rθ, A = ½r²θ) with direct substitution. Both parts require only recall of standard formulas and basic arithmetic with no problem-solving or conceptual challenges, making it easier than average but not trivial since students must remember to use radians. |
| Spec | 1.05d Radians: arc length s=r*theta and sector area A=1/2 r^2 theta |
The diagram below shows a circle centre O, radius 4 cm. Points A and B lie on the circumference such that arc AB is 5 cm.
\includegraphics{figure_2}
\begin{enumerate}[label=(\alph*)]
\item Calculate the angle subtended at O by the arc AB. [2]
\item Determine the area of the sector OAB. [2]
\end{enumerate}
\hfill \mbox{\textit{WJEC Unit 3 2018 Q2 [4]}}