Advertisements
Advertisements
Question
In the example given below, the radius of the base of a cylinder and its height is given. Then find the curved surface area and total surface area.
r = 2.5 cm, h = 7 cm
Solution
We know that,
Curved surface area = 2πrh
Total surface area = 2πr(h + r)
Here, r = 2.5 cm, h = 7 cm
Curved surface area of a cylinder = 2πrh
= `2 xx 22/7 xx 2.5 xx 7`
= `44 xx 2.5`
= 110 sq.cm.
Total surface area of a cylinder = 2πr(h + r)
= `2 xx 22/7 xx 2.5(7 + 2.5)`
= `110/7 xx 9.5`
= `1045/7 = 149.285`
≈ 149.29 sq. cm.
RELATED QUESTIONS
The circumference of the base of a cylinder is 88 cm and its height is 15 cm. Find its curved surface area and total surface area.
The inner diameter of a circular well is 3.5 m. It is 10 m deep. Find the cost of plastering its inner curved surface at Rs 4 per square metre.
The rain which falls on a roof 18 m long and 16.5 m wide is allowed to be stored in a cylindrical tank 8 m in diameter. If it rains 10 cm on a day, what is the rise of water level in the tank due to it?
Find the length of 13.2 kg of copper wire of diameter 4 mm, when 1 cubic cm of copper weighs 8.4 gm.
2.2 cubic dm of brass is to be drawn into a cylindrical wire 0.25 cm in diameter. Find the length of the wire.
Write the ratio of total surface area to the curved surface area of a cylinder of radius rand height h.
The radius of a wire is decreased to one-third. If volume remains the same, the length will become
The height of sand in a cylindrical shaped can drops 3 inches when 1 cubic foot of sand is poured out. What is the diameter, in inches, of the cylinder?
In the above question, curved surface area of A is ______ curved surface area of B.
A rectangular sheet of paper of size 11 cm × 7 cm is first rotated about the side 11 cm and then about the side 7 cm to form a cylinder, as shown in the diagram. The ratio of their curved surface areas is ______.
