Advertisements
Advertisements
Question
Find the area and perimeter of the circles with following: Radius = 10.5cm
Solution
The Area of a Circle with radius r = πr2
∴ The Area of a Circle with radius 10.5cm
= π(10.5)2
= `(22)/(7)(10.5)^2`
= 346.5cm2
The Circumference of a Circle with radius r = 2πr
The Circumference of a Circle with radius 10.5
= 2π(10.5)
= `2 xx (22)/(7)(10.5)`
= 66cm.
APPEARS IN
RELATED QUESTIONS
An elastic belt is placed around the rim of a pulley of radius 5 cm. (Fig. 10) From one point C on the belt, the elastic belt is pulled directly away from the centre O of the pulley until it is at P, 10 cm from the point O. Find the length of the belt that is still in contact with the pulley. Also find the shaded area (use π = 3.14 and `sqrt3=1.73)`
A brooch is made with silver wire in the form of a circle with diameter 35 mm. The wire also used in making 5 diameters which divide the circle into 10 equal sectors as shown in Fig. Find:
(i) the total length of the silver wire required
(ii) the area of each sector of the brooch
Given figure depicts an archery target marked with its five scoring areas from the centre outwards as Gold, Red, Blue, Black and White. The diameter of the region representing Gold score is 21 cm and each of the other bands is 10.5 cm wide. Find the area of each of the five scoring regions. [use π = 22/7]
Choose the correct alternative answer for the following question.
Find the area and perimeter of the circle with the following:
Diameter= 35 cm
Each side of a square is 44 cm. Find its perimeter. If this perimeter is equal to the circumference of a circle, find the radius of the circle.
The inner circumference of a circular track is 264 m and the width of the track is 7 m. Find:
(i) the radius of the inner track.
(ii) the radius of the outer circumference.
(iii) the length of the outer circumference.
(iv) the cost of fencing the outer circumference at the rate of ₹50 per m.
Find the radius and area of the circle which has circumference equal to the sum of circumferences of the two circles of radii 3 cm and 4 cm respectively.
A ground is in the form of a circle whose diameter is 350 m. An athlete makes 4 revolutions. Find the distance covered by the athlete
The distance around a circle is its ______.
