Advertisements
Advertisements
प्रश्न
Choose the correct answer of the following question:
If the radius of a sphere becomes 3 times, then its volume will become
विकल्प
3 times
6 times
9 times
27 times
उत्तर
Let the radius of the given sphere and that of the new sphere be r and R, respectively;
Also, the volume of the given sphere and that the new sphere be v and V,
We have,
R = 3r .........(i)
Now,
`"Volume of the new sphere"/"Volume of the given sphere" = ((4/3 pi"R"^3))/((4/3 pi"r"^3))`
`= ("R"/r)`
`= ((3r)/r)^3` [Using (i)]
= 33
= 27
Hence, the correct answer is option (d).
APPEARS IN
संबंधित प्रश्न
The radii of two cylinders are in the ratio 3 : 5. If their heights are in the ratio 2 : 3, then the ratio of their curved surface areas is
A solid is in the form of a right circular cone mounted on a hemisphere. The radius of the hemisphere is 2.1 cm and the height of the cone is 4 cm. The solid is placed in a cylindrical tub full of water in such a way that the whole solid is submerged in water. If the radius of the cylinder is 5 cm and its height is 9.8 cm, find the volume of the water left in the tub.
A copper rod of diameter 2 cm and length 10 cm is drawn into a wire of uniform thickness and length 10 m. Find the thickness of the wire.
A solid right circular cone of height 60 cm and radius 30 cm is dropped in a right circular cylinder full of water, of height 180 cm and radius 60 cm. Find the volume of water left in the cylinder, in cubic metres.
A solid metallic sphere of radius 8 cm is melted and recast into spherical balls each of radius 2 cm. Find the number of spherical balls obtained.
The sum of the inner and the outer curved surfaces of a hollow metallic cylinder is 1056 cm2 and the volume of material in it is 1056 cm3. Find its internal and external radii. Given that the height of the cylinder is 21 cm.
A mason constructs a wall of dimensions 270 cm × 300 cm × 350 cm with the bricks each of size 22.5 cm × 11.25 cm × 8.75 cm and it is assumed that `1/8` space is covered by the mortar. Then the number of bricks used to construct the wall is ______.
A solid iron cuboidal block of dimensions 4.4 m × 2.6 m × 1 m is recast into a hollow cylindrical pipe of internal radius 30 cm and thickness 5 cm. Find the length of the pipe.
A building is in the form of a cylinder surmounted by a hemispherical vaulted dome and contains `41 19/21 m^3` of air. If the internal diameter of dome is equal to its total height above the floor, find the height of the building?
The sum of the length, breadth and height of a cuboid is `6sqrt(3)` cm and the length of its diagonal is `2sqrt(3)` cm. The total surface area of the cuboid is ______.