Q20 of 49 Page 1

In a circle of radius 21 cm, an arc subtends an angle of 60 � at the centre.

Find: (i) the length of the arc (ii) area of the sector formed by the arc. [use π = 22/7]


kukgkh.png

Given-

Radius of Circle(r) = 21 cm


Angle sustended at the centre by the arc(θ) = 60°


(i) Length of arc = (θ/360°) × 2× π × r


= (60°/360°) × 2× (22/7)× 21


= (1/6) × 132


= 22 cm


(ii) Area of the sector formed by the arc = (θ/360°) × π × (r)2


= (60°/360°) × (22/7) × (21)2


= (1/6) × 22× 63


= 231 cm2


More from this chapter

All 49 →
18

A vessel is in the form of a hemispherical bowl surmounted by a hollow cylinder of same diameter. The diameter of the hemispherical bowl is 14 cm and the total height of the vessel is 13 cm. Find the total (inner) surface area of the vessel. [use π = 22/7]

kjjgkk.png

 19

A wooden toy was made by scooping out a hemisphere of same radius from each end of a solid cylinder. If the height of the cylinder is 10 cm, and its base is of radius 3.5 cm, find the volume of wood in the toy. [use π = (22/7)]

kkj.png

 21

Solve the following for x:

 22

Sum of the areas of two squares is 400 cm2. If the difference of their perimeters is 16 cm, find the sides of the two squares.