Advertisements
Advertisements
Question
Find the number of coins, 1.5 cm is diameter and 0.2 cm thick, to be melted to form a right circular cylinder of height 10 cm and diameter 4.5 cm.
Solution
Volume of one coin `=pi xx (1.5)^(2/4) xx 0.2`
Volume of cylinder`= pi xx (4.5)^2 xx 10 /4`
So number of coins to be melted
`="volume of cylinder"/"volume of each coin"`
`=(4.5/1.5) xx 10/0.2`
`= 9 xx 50`
` = 450`
APPEARS IN
RELATED QUESTIONS
A solid sphere of diameter 6 cm is dropped in a right circular cylindrical vessel partly filled with water. The diameter of the cylindrical vessel is 12 cm. If the sphere is completely submerged in water, by how much will the level of water rise in the cylindrical vessel?
A building is in the form of a cylinder surrounded by a hemispherical dome. The base diameter of the dome is equal to \[\frac{2}{3}\] of the total height of the building . Find the height of the building , if it contains \[67\frac{1}{21} m^3\].
A spherical shell of lead, whose external diameter is 18 cm, is melted and recast into a right circular cylinder, whose height is 8 cm and diameter 12 cm. Determine the internal diameter of the shell.
A conical vessel whose internal radius is 10 cm and height 48 cm is full of water. Find the volume of water. If this water is poured into a cylindrical vessel with internal radius 20 cm, find the height to which the water level rises in it.
The surface area of a sphere is 2464 cm2. If its radius be doubled, then what will be the surface area of the new sphere?
A vessel is in the form of a hemispherical bowl surmounted by a hollow cylinder. The diameter of the hemisphere is 21 cm and the total height of the vessel is 14.5 cm. Find its capacity.
A sphere of diameter 18 cm is dropped into a cylindrical vessel of diameter 36 cm, partly filled with water. If the sphere is completely submerged, then the water level rises by ______.
The volume of a cube is 2744 cm2. Its surface area is
The ratio between the radius of the base and the height of a cylinder is 2 : 3. If its volume is 1617 cm3, the total surface area of the cylinder is
The diameter of a sphere is 42 cm. It is melted and drawn into a cylindrical wire of diameter 2.8 cm. Find the length of the wire.
