Advertisements
Advertisements
प्रश्न
Find the surface area of a sphere of radius 10.5 cm.
`["Assume "pi=22/7]`
उत्तर
Radius (r) of sphere = 10.5 cm
Surface area of sphere = 4πr2
= `[4xx22/7xx(10.5)^2] cm^2`
= `(4xx22/7xx10.5xx10.5) cm^2`
= (88 × 1.5 × 10.5) cm2
= 1386 cm2
Therefore, the surface area of a sphere having a radius of 10.5 cm is 1386 cm2.
APPEARS IN
संबंधित प्रश्न
A model of a ship is made to a scale 1: 300
1) The length of the model of the ship is 2 m. Calculate the lengths of the ship.
2) The area of the deck ship is 180,000 m2. Calculate the area of the deck of the model.
3) The volume of the model in 6.5 m3. Calculate the volume of the ship.
Find the surface area of a sphere of diameter 14 cm .
Find the surface area of a sphere of diameter 21 cm .
Metallic spheres of radii 6 cm, 8 cm and 10 cm respectively are melted and recasted into a single solid sphere. Taking π = 3.1, find the surface area of the solid sphere formed.
A hemi-spherical bowl has negligible thickness and the length of its circumference is 198 cm. Find the capacity of the bowl.
Find the maximum volume of a cone that can be carved out of a solid hemisphere of radius r cm.
The diameter of a sphere is 6 cm. It is melted and drawn into a wire of diameter 0.2 cm. Find the length of the wire.
If the ratio of volumes of two spheres is 1 : 8, then the ratio of their surface areas is
A cone and a hemisphere have equal bases and equal volumes the ratio of their heights is
A manufacturing company prepares spherical ball bearings, each of radius 7 mm and mass 4 gm. These ball bearings are packed into boxes. Each box can have maximum of 2156 cm3 of ball bearings. Find the:
- maximum number of ball bearings that each box can have.
- mass of each box of ball bearings in kg.
(use π = `22/7`)
