Advertisements
Advertisements
प्रश्न
The ratio of the total surface area of a sphere and a hemisphere of same radius is
विकल्प
2 : 1
3 : 2
4 : 1
4 : 3
Advertisements
उत्तर
In the given question,
The total surface area of a sphere (S1) = 4 \[\pi r^2\]
The total surface area of a hemisphere (S2) = 3 \[\pi r^2\]
So the ratio of the total surface area of a sphere and a hemisphere will be,
`S_1/S_2 = (4 pi r^2)/ (3 pi r^2)`
`= 4/3`
Therefore, the ratio of the surface areas is 4: 3 .
APPEARS IN
संबंधित प्रश्न
Find the surface area of a sphere of diameter 14 cm.
`["Assume "pi=22/7]`
A hemispherical bowl is made of steel, 0.25 cm thick. The inner radius of the bowl is 5 cm. Find the outer curved surface area of the bowl.
`["Assume "pi = 22/7]`
Find the surface area of a sphere of diameter 21 cm.
Find the surface area of a sphere of diameter 3.5 cm.
Assuming the earth to be a sphere of radius 6370 km, how many square kilo metres is area
of the land, if three-fourth of the earth’s surface is covered by water?
A hemi-spherical dome of a building needs to be painted. If the circumference of the base of
the dome is 17.6 cm, find the cost of painting it, given the cost of painting is Rs. 5 per l00
`cm^2`
The volume of a sphere is 38808 cm3; find its diameter and the surface area.
How many spherical bullets can be made out of a solid cube of lead whose edge measures 44 cm, each bullet being 4 cm in diameter?
If a sphere is inscribed in a cube, find the ratio of the volume of cube to the volume of the sphere.
The ratio between the volume of a sphere and volume of a circumscribing right circular cylinder is
A cone and a hemisphere have equal bases and equal volumes the ratio of their heights is
The model of a building is constructed with the scale factor 1 : 30.
(i) If the height of the model is 80 cm, find the actual height of the building in meters.
(ii) If the actual volume of a tank at the top of the building is 27m3, find the volume of the tank on the top of the model.
Find the surface area and volume of sphere of the following radius. (π = 3.14)
4 cm
Find the radius of a sphere whose surface area is equal to the area of the circle of diameter 2.8 cm
How many lead balls of radii 1 cm each can be made from a sphere of 8 cm radius?
A sphere has the same curved surface area as the curved surface area of a cone of height 36 cm and base radius 15 cm . Find the radius of the sphere .
Find the volume of the hollow sphere whose inner diameter is 8 cm and the thickness of the material of which it is made is 1 cm .
A certain number of metallic cones, each of radius 2 cm and height 3 cm are melted and recast into a solid sphere of radius 6 cm. Find the number of cones used.
The radius of a sphere increases by 25%. Find the percentage increase in its surface area
