Advertisements
Advertisements
Question
The hollow sphere, in which the circus motor cyclist performs his stunts, has a diameter of 7 m. Find the area available to the motorcyclist for riding.
Advertisements
Solution
In the given problem, the area available for the motorcyclist for riding will be equal to the surface area of the hollow sphere. So here, we have to find the surface area of a hollow sphere of a given diameter.
Diameter of the sphere (d) = 7 m
So, surface area of the sphere = `4 pi (d/2)^2`
`=4(22/7)(7/2)^2`
`=(22/7)(3.5)^2`
=154 m2
Therefore, the area available for the motorcyclist for riding is 154 m2 .
APPEARS IN
RELATED QUESTIONS
Find the surface area of a sphere of diameter 14 cm.
`["Assume "pi=22/7]`
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.
On a map drawn to a scale of 1: 50,000, a rectangular plot of land ABCD has the following dimensions. AB = 6 cm; BC = 8 cm and all angles are right angles. Find:
1) the actual length of the diagonal distance AC of the plot in km.
2) the actual area of the plot in sq. km.
A hollow sphere of internal and external radii 6 cm and 8 cm respectively is melted and recast into small cones of base radius 2 cm and height 8 cm. Find the number of cones.
Find the surface area of a sphere of diameter 21 cm.
A hemispherical bowl made of brass has inner diameter 10.5 cm. Find the cost of tin- plating
it on the inside at the rate of Rs. 4 per 100 `cm^2`
The volume of a sphere is 38808 cm3; find its diameter and the surface area.
What is the least number of solid metallic spheres, each of 6 cm diameter, that should be melted and recast to form a solid metal cone whose height is 45 cm and diameter 12 cm?
Find the radius of a sphere whose surface area is 154 cm2.
The surface area of a sphere of radius 5 cm is five times the area of the curved surface of a cone of radius 4 cm. Find the height of the cone.
If the ratio of volumes of two spheres is 1 : 8, then the ratio of their surface areas is
If the surface area of a sphere is 144π m2, then its volume (in m3) is
Find the surface area and volume of sphere of the following radius. (π = 3.14 )
9 cm
Find the volume of a sphere, if its surface area is 154 sq.cm.
The surface area of a solid metallic sphere is 2464 cm2. It is melted and recast into solid right circular cones of radius 3.5 cm and height 7 cm. Calculate : the number of cones recast. `("Take" pi =22/7)`
A sphere cut out from a side of 7 cm cubes. Find the volume of this sphere?
The cylinder of radius 12 cm have filled the 20 cm with water. One piece of iron drop in the stands of water goes up 6.75 cm. Find the radius of sphere piece.
The surface area of a solid metallic sphere is 616 cm2. It is melted and recast into smaller spheres of diameter 3.5 cm. How many such spheres can be obtained?
The radius of a hemispherical balloon increases from 6 cm to 12 cm as air is being pumped into it. The ratios of the surface areas of the balloon in the two cases is ______.
