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प्रश्न
How many solid cylinders of radius 6 cm and height 12 cm can be made by melting a solid sphere of radius 18 cm?
Activity: Radius of the sphere, r = 18 cm
For cylinder, radius R = 6 cm, height H = 12 cm
∴ Number of cylinders can be made =`"Volume of the sphere"/square`
`= (4/3 pir^3)/square`
`= (4/3 xx 18 xx 18 xx 18)/square`
= `square`
उत्तर
∴ Number of cylinders can be made =`"Volume of the sphere"/"Volume of cylinder"`
`= (4/3 pi"r"^3)/(pi "r"^2"h")`
`= (4/3 xx 18 xx 18 xx 18)/(6 xx 6 xx 12)`
`= (4 xx 18 xx 18 xx 18)/(3 xx 6 xx 6 xx 12)`
= 18
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