Advertisements
Advertisements
Question
A right circular cylindrical tunnel of diameter 2 m and length 40 m is to be constructed from a sheet of iron. The area of the iron sheet required in m2, is
Options
40 \[\pi\]
80 \[\pi\]
160 \[\pi\]
200 \[\pi\]
Solution
Let r be the radius of the cylinder and h be its height.
It is given that:
`2r = 2 ⇒ r = 1 m`
And,
h = 40 m
Therefore, total surface area S of the sheet required is:
`S = 2 pirh`
`⇒ S = 2pi xx 1xx40`
`⇒ S = 80pi m^2`
APPEARS IN
RELATED QUESTIONS
The radii of two cylinders are in the ratio 2 : 3 and their heights are in the ratio 5 : 3. Calculate the ratio of their volumes.
A rectangular sheet of paper 30 cm × 18 cm can be transformed into the curved surface of a right circular cylinder in two ways i.e., either by rolling the paper along its length or by rolling it along its breadth. Find the ratio of the volumes of the two cylinders thus formed.
Water flows out through a circular pipe whose internal diameter is 2 cm, at the rate of 6 metres per second into a cylindrical tank, the radius of whose base is 60 cm. Find the rise in the level of water in 30 minutes?
A cylindrical tube, open at both ends, is made of metal. The internal diameter of the tube is 10.4 cm and its length is 25 cm. The thickness of the metal is 8 mm everywhere. Calculate the volume of the metal.
Radius of base of a cylinder is 20 cm and its height is 13 cm, find its curved surface area and total surface area. (π = 3.14)
The dimensions of a car petrol tank are 50 cm × 32 cm × 24 cm, which is full of petrol. If a car's average consumption is 15 km per liter, find the maximum distance that can be covered by the car.
A solid iron cylinder has total surface area of 1848 sq.m. Its curved surface area is five – sixth of its total surface area. Find the radius and height of the iron cylinder.
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 = 1.4 cm, h = 2.1 cm
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 = 70 cm, h = 1.4 cm
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 ______.
