Advertisements
Advertisements
प्रश्न
If four times the sum of the areas of two circular faces of a cylinder of height 8 cm is equal to twice the curve surface area, then diameter of the cylinder is
पर्याय
4 cm
8 cm
2 cm
6 cm
उत्तर
Let r be the radius of cylinder.
Area of circular base of cylinder `=pir^2`
The height of cylinder h = 8 cm
The C.S.A. of cylinder`= 2pir xx 8 = 16 pir`
Clearly,
`4 xx (pir^2 + pir^2) = 2 xx (pir)`
`8 pir^2 = 32 pi r`
`8r^2 = 32r`
r = 4cm
The diameter of cylinder
`d = 4 xx 2 = 8 "cm"`
APPEARS IN
संबंधित प्रश्न
A right circular cylinder of radius r and height h (h = 2r) just encloses a sphere of diameter
The radii of the ends of a bucket 16 cm height are 20 cm and 8 cm. The curved surface area of the bucket is
Metallic spheres of radii 6 cm, 8 cm and 10 cm, respectively are melted to form a single solid sphere. Find the radius of the resulting sphere.
During conversion of a solid from one shape to another, the volume of the new shape will ______.
A cylindrical bucket, 32 cm high and 18 cm of radius of the base, is filled with sand. This bucket is emptied on the ground and a conical heap of sand is formed. If the height of the conical heap is 24 cm, find the radius and slant height of the heap.
A solid cylinder of radius r and height h is placed over other cylinder of same height and radius. The total surface area of the shape so formed is 4πrh + 4πr2.
How many spherical lead shots of diameter 4 cm can be made out of a solid cube of lead whose edge measures 44 cm.
A solid metallic hemisphere of radius 8 cm is melted and recasted into a right circular cone of base radius 6 cm. Determine the height of the cone.
A solid piece of metal in the form of a cuboid of dimensions 11 cm × 7 cm × 7 cm is melted to form 'n' number of solid spheres of radii `7/2` cm each. Find the value of n.
The volume of a right circular cone whose area of the base is 156 cm2 and the vertical height is 8 cm, is ______.
