Advertisements
Advertisements
Question
Find the area enclosed between two concentric circles, If their radii are 6cm and 13cm respectively.
Advertisements
Solution
We know,
The area of the ring between two concentric circles equals the area of the larger circle minus the area of smaller circle. Let the radius of the outer and inner ring be R and r respectively.
Here, the radius of the outer circle
= 13cm and the radius of the inner circle
= 6cm
The Area of a Circle with radius r = πr2
The area of the ring = π(13)2 - 62)
= `(22)/(7)(169 - 36)`
= `(22)/(7)(133)`
= 22 x 9
= 418cm2.
APPEARS IN
RELATED QUESTIONS
In a circle of radius 21 cm, an arc subtends an angle of 60° at the centre. Find the length of the arc. (Use π = `22/7`)
In the following figure, PQRS is a square of side 4 cm. Find the area of the shaded square.
In the following figure, ABCD is a rectangle, having AB = 20 cm and BC = 14 cm. Two sectors of 180° have been cut off. Calculate:
the area of the shaded region.
In the following figure, the square ABCD is divided into five equal parts, all having same area. The central part is circular and the ines AE, GC, BF and HD lie along the diagonals AC and BD of the square. If AB = 22 cm, find:
the circumference of the central part.
Find the areas of both the segments of a circle of radius 42 cm with central angle 120°.
If a square is inscribed in a circle, find the ratio of the areas of the circle and the square.
In the given figure, O is the centre of the circle with AC = 24 cm, AB = 7 cm and ∠BOD = 90°. Find the area of shaded region.
Find the area of a circle of radius 30 cm (use π = 3.14).
It is proposed to build a single circular park equal in area to the sum of areas of two circular parks of diameters 16 m and 12 m in a locality. The radius of the new park would be ______.
Area of a quadrant of a circle of radius 7 cm is ______.
