Areas Related to Circles Class 10 Notes i.e. for chapter 12 provided here are extremely useful for the class 10 students to prepare and revise this chapter in a more efficient way. The most important topics from this chapter include the following topics which are explained in detail below.

- Area of a circle
- Perimeter or circumference of a circle
- Area of a sector of a circle
- Area of a segment of a circle

## Area and Circumference of a Circle

For a circle, its area can be calculated by measuring the region that is enclosed by its boundary. The perimeter of a circle or its circumference is defined as the length of the circle’s boundary. The formula for area and perimeter of a circle is given as-

Area of a Circle |
\(\pi r^{2}\) |

Circumference of a Circle |
\(2\pi r\) |

### Area of a Sector of a Circle

A sector of a circle can be defined as the part of that particular circle which is in between any two chosen radii.

In the above diagram, the shaded region is the sector of a triangle and its area and the length of an arc of a sector is given by-

\(Area\, of\, the\, sector\, of\, angle\, \theta\) | \(\frac{\theta}{360}\times \pi\times r^{2}\) |

\(Length\, of\, an\, arc\, of\, a\, sector\, of\, angle\, \theta\) | \(\frac{\theta}{360}\times 2\pi r\) |

### Area of a Segment of a Circle

Consider the same figure as given above-

In this, AB is a chord which divides the circle into two parts i.e. a major part and a minor part. Now, the Area of the segment APB can be found by-

Area of the segment APB = Area of the sector OAPB – Area of ∆ OAB

Or,

\(Area\, of\, the\, segment\, APB = \frac{\theta}{360}\times \pi r^{2} – area\, of\, triangle\, \bigtriangleup OAPB\)

### Example Questions

### Practice Questions

- Calculate the radius of a circle if its circumference is 528 cm.
- What is the area of the sector of angle 60 degrees if the radius of the circle is 10 cm?
- Find the area of the following figure: (Note: ABCD is a square of side 14 cm and APD and BPC are semicircles).

### Also Check:

Area Of a Circle | Circumference Of A Circle |

NCERT Solutions For Class 10 Maths Chapter 12 | Important Questions from Areas Related to Circles |

Keep visiting BYJU’S to get more such maths notes for class 10 along with other preparation materials and prepare for the class 10 board exam in a more effective way.