Advertisements
Advertisements
प्रश्न
A bucket open at the top is in the form of a frustum of a cone with a capacity of 12308.8 cm3 . the radii of the top and bottom of the circular ends of the bucket are 20 cm and 12 cm respectively. Find the height of the bucket and also the area of the metal sheet used in making it.
उत्तर
Let the height of the bucket ne h cm and Slant height be I cm.
Here,
r1 = 20 cm
r2 = 12 cm
And capacity of bucket = 12308.8 cm3
We know that capacity of bucket = `(pi"h")/3 (r_2^2 + r_2^2 + r_1r_2)`
`= 3.14 xx "h"/3 (400 + 144 + 240)`
`= 3.14xx"h"/3 xx 784`
So we have = `3.14xx"h"/3xx784` = 12308.8
`"h" = (12308.8xx3)/(3.14xx784)`
= 15 cm
Now, the slant height of the frustum,
l = `sqrt("h"^2 + ("r"_1 - "r"_2)^2`
`= sqrt(15^2 + 8^2)`
`=sqrt289`
= 17 cm
Area of metal sheet used in making it
`= pir_2^2 + pi(r_1 + r_2)^2`
`= 3.174 xx [144 + (20 + 12) xx 17]`
= 2160.32 cm2
APPEARS IN
संबंधित प्रश्न
An oil funnel made of tin sheet consists of a 10 cm long cylindrical portion attached to a frustum of a cone. If the total height is 22 cm, diameter of the cylindrical portion is 8 cm and the diameter of the top of the funnel is 18 cm, find the area of the tin sheet required to make the funnel (see the given figure).
A solid is in the shape of a frustum of a cone. The diameter of two circular ends are 60cm and 36cm and height is 9cm. find area of its whole surface and volume?
A tank of cylindrical shape has radius 2.8 m and its height 3.5 m. Complete the activity to find how many litres of water the tank will contain.
Capacity of water tank = Volume of cylindrical tank
= πr2h
The vertical height of a conical tent is 42 dm and the diameter of its base is 5.4 m. Find the number of persons it can accommodate if each person is to be allowed 29.16 cubic dm.
A tent of height 8.25 m is in the form of a right circular cylinder with diameter of base 30 m and height 5.5 m, surmounted by a right circular cone of the same base. Find the cost of the canvas of the tent at the rate of Rs 45 per m2.
Choose the correct answer of the following question:
The radii of the circular ends of a bucket of height 40 cm are 24 cm and 15 cm. The slant height (in cm) of the bucket is
In Figure 3, a decorative block is shown which is made of two solids, a cube, and a hemisphere. The base of the block is a cube with an edge 6 cm and the hemisphere fixed on the top has a diameter of 4⋅2 cm. Find
(a) the total surface area of the block.
(b) the volume of the block formed. `("Take" pi = 22/7)`
A right circular cylinder of radius r cm and height h cm (h > 2r) just encloses a sphere of diameter ______.
The surface areas of the six faces of a rectangular solid are 16, 16, 32, 32, 72 and 72 square centimetres. The volume of the solid, in cubic centimetres, is ______.
______ surface area of room = area of 4 walls.