Find the radius of the circle, if OA = 12.5 cm and AT = 10 cm.
Answers
Step-by-step explanation:
athematics NCERT Grade 10, Chapter 12: Areas related to circles- We already know the methods of finding perimeter and area of simple plane figures such as rectangles, squares, parallelograms, triangles, and circles. In this chapter, we will study about the areas related to circles. The first section is about the perimeter and area of a circle.
Area of the circle = 1/2 × 2πr ×r = πr2
Great Indian mathematician Aryabhata gave an approximate value of (pie) π which is a constant ratio that the circumference has with the diameter of the circle. One solved example is discussed in this section in which the cost of ploughing the field is found and the student thus recalls the formulas for finding the circumference and area of a circle. First exercise 12.1 is a short exercise containing 5 questions consisting of word problems.
Second section deals with areas of sector and segment of a circle.
Two types of the sectors are discussed here:
Major sector
Minor sector
Two types of the segments are discussed here:
Minor segment
Major segment
Area of a segment of a circle can be calculated by subtracting the area of the corresponding triangle from the area of the corresponding sector.
Two examples are discussed in this section to make the concept clear to students. Exercise 12.2 contains 14 questions that are related to the area of circles.