Areas Related to Circles

1. Find the perimeter of a semicircle having a radius of 14cm.

2. Find the area of a ring shaped region enclosed between two concentric circles of radii 20 cm and 15cm.

3. If the diameter of the semi-circular protractor is 14cm. Find its perimeter.

4. Find the perimeter of a quadrant of a circle whose diameter is 7cm.

5. The circumference of a circle is 176cm. Find its diameter.

6. The length of a wire which is tied as a boundary of Semi-circular Park is 72cm. Find the radius of the semi- circular park and its area.

7. Prove that the area of a circular path of uniform width b, surrounding a circular region of radius r is πb(2r+b).

8. A wire is in the form of a circle of radius 35cm. Find the side of the square into which it can be bent.

9. A bicycle wheel makes 5000 revolutions in moving 11km. Find the diameter of the wheel.(Take π = 22/7)

10. If the area of the semi-circular region is 77cm^2, find its perimeter.

11. The short and long hand of a clock are 4cm and 6cm long respectively. Find the sum of the distances travelled by their tips in two days.

12. The perimeter of a sector of a circle of radius 5.2cm is 16.4cm. Find the area of the sector.

13. Four horses are tethered at four corners of a square field of side 50cm, so that they just can reach one another. What is the area of the field will be ungrazed.

14. Four equal circles each of radius 5cm touch each other. Find the area between them.