Get the CBSE Class 10th Mathematics, Area related to Circles: Important Questions & Preparation Tips. This will help with a precise description of the whole chapter along with a gist of each topic covered in the chapter. The Questions mentioned are exclusively topic oriented and are famous for its repetition in many Board papers. Consider the below mentioned points and questions at the time of preparation.
Circumference: The distance covered by travelling once around a circle is called its perimeter, usually called its circumference.
The circumference of a circle bears a constant ratio with its diameter. This constant ratio is denoted by a Greek letter π.
Circumference = 2πr
Area of a circle, whose radius is r, will be given by πr2 or Area πr2.
Sector of a circle: The portion of the circular region enclosed between two radii and the corresponding arc is called a sector of the circle.
The sector with a greater circumference is called the major sector and its corresponding the one having a smaller circumference is called the minor sector.
Segment of a circle: The portion of the circular region enclosed between a chord and the corresponding arc is called the segment of a circle.
The segment containing the centre of the circle is called major segment and other the minor segment.
To find the areas of different shapes, add or subtract the areas of different parts of the shape to get the result.
- If the area of a circle is 616 cm2, then what is its perimeter? (1 mark)
- The circumference of a circle exceeds the diameter by 16.8 cm. Find the radius of the circle. (2 mark)
- A chord of a circle of radius 15 cm subtends an angle of 60o at the centre. Find the areas of the corresponding minor and major segments of the circle. (3 mark)
- To warn ships of underwater rocks, a lighthouse spreads a red coloured light over a sector of angle 80o to a distance of 16.5 km. Find the area of the sea over which the ships are warned. (3 mark)
- A chord AB of a circle of radius 10 cm makes a right angle at the centre of the circle. Find the area of the major and minor segments. (4 mark)
- PQRS is the diameter of a circle of radius 6 cm. The lengths PQ, QR and RS are equal (PQ = QR = RS). Semi-circle is drawn on PQ and QS as diameters, as shown in figure. Find the perimeter and area of the shaded region. (4 mark)
You can also find: