Chapter 11: Areas Related to Circles

Questions

1. Circumference: $r = 21$ ($\pi = 22/7$).
2. Sector area: $\theta = 90^\circ, r = 10$.
3. Arc length: $\theta = 45^\circ, r = 14$.
4. Radius when circumference $= 88$.
5. Area of annulus $R = 10, r = 7$.
6. Minor segment area $r = 10, \theta = 60^\circ$.
7. Wheel makes $200$ revolutions to cover $88$ m. Diameter?
8. Area of a quadrant of a circle with $r = 14$.
9. Perimeter of a sector: $r = 21$, $\theta = 60^\circ$.
10. Area of a shaded region: circle of radius $7$ inscribed in a square of side $14$.

Extra Practice (Optional)

• Area of the sector $\theta = 120^\circ$, $r = 6$.
• Area of shaded region between two concentric circles.
• Circumference of a semicircle with $r = 14$.
• Length of chord subtending $90^\circ$ at centre, $r = 10$.
• Radius of circle with area $= 616$ cm$^2$.