Advertisements
Advertisements
Question
Find the surface area of a sphere of radius 14 cm.
`["Assume "pi=22/7]`
Solution
Radius (r) of sphere = 14 cm
Surface area of sphere = 4πr2
= `[4xx22/7xx(14)^2]cm^2`
= (4 × 44 × 14) cm2
= 2464 cm2
Therefore, the surface area of a sphere having radius 14 cm is 2464 cm2.
APPEARS IN
RELATED QUESTIONS
The radius of a spherical balloon increases from 7 cm to 14 cm as air is being pumped into it. Find the ratio of surface areas of the balloon in the two cases.
A wooden toy is in the form of a cone surmounted on a hemisphere. The diameter of the base
of the cone is 16 cm and its height is 15 cm. Find the cost of painting the toy at Rs. 7 per 100
`cm^2`.
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`
Find the maximum volume of a cone that can be carved out of a solid hemisphere of radius r cm.
If the surface area of a sphere is 144π m2, then its volume (in m3) is
If a solid sphere of radius 10 cm is moulded into 8 spherical solid balls of equal radius, then the surface area of each ball (in sq.cm) is
If the radius of a solid hemisphere is 5 cm, then find its curved surface area and total surface area. ( π = 3.14 )
Find the surface area of a sphere, if its volume is 38808 cubic cm. `(π = 22/7)`
The given figure shows the cross-section of a cone, a cylinder and a hemisphere all with the same diameter 10 cm and the other dimensions are as shown.
Calculate :
- the total surface area.
- the total volume of the solid and
- the density of the material if its total weight is 1.7 kg.
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?