Advertisements
Advertisements
Question
Find the area and perimeter of the following semicircles: Diameter = 5.6cm
Advertisements
Solution
The radius of a Circle with diameter d is r = `"d"/(2)`
The Area of a Semi-circle with radius r = `(pi"r"^2)/(2)`
The Perimeter of a Semi-circle with radius r
= πr + 2r
= r(π + 2)
= `"r"(22/7 + 2)`
= `(36)/(7) xx "r"`
The radius of a Circle with diameter 5.6 is r
= `(5.6)/(2)`
= 2.8cm
The Area of a Semi-circle with radius 2.8
= `(pi(2.8)^2)/(2)`
= 12.32cm2
The Perimeter of a Semi-circle with radius r
= π x 2.8 + 2 x 2.8
= 2.8(π + 2)
= `2.8(22/7 + 2)`
= `(36)/(7) xx 2.8`
= 14.4cm.
APPEARS IN
RELATED QUESTIONS
In Fig. there are shown sectors of two concentric circles of radii 7 cm and 3.5 cm. Find the area of the shaded region. Use π = `(\frac { 22 }{ 7 }).`
Find the circumference and area of circle of radius 4.2 cm
The area of circle, inscribed in equilateral triangle is 154 cms2. Find the perimeter of
triangle.
The area of rhombus is `480cm^2` , and one of its diagonal measures 48 cm. Find
(i) the length of the other diagonal,
(ii) the length of each of the sides
(iii) its perimeter
The perimeter of a circular field is 242 m. The area of the field is
If the sum of the circumferences of two circles with radii R1 and R2 is equal to the circumference of a circle of radius R, then ______.
Find the area and perimeter of the following semi-circle :
Diameter= 7 cm
The diameter of a right circular cylinder is 12 m and the slant height is 10 m. Find its curved surface area and the total surface area .
A race track is in the form of a circular ring whose outer and inner circumferences are 396 m and 352 m respectively. The width of the track is ____________.
The circumferences of two circles are in the ratio 4 : 5. What is the ratio of their radii?
