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Question
A solid cone of radius 5 cm and height 8 cm is melted and made into small spheres of radius 0.5 cm. Find the number of spheres formed.
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Solution
A volume of solid cone = `1/3 pir^2h = 1/3 xx 22/7 xx 5^2 xx 8 = 1/3 xx 22/7 xx 25 xx 8`
Volume of a small sphere = `4/3 pir^3 = 4/3 xx 22/7 xx (5/10)^3 = 4/3 xx 22/7 xx 125/1000`
Number of spheres formed = `"Volumeof cone"/"Volumeof sphere"` = `(1/3 xx 22/7 xx 25xx8)/(4/3 xx 22/7 xx 125/1000) = 400`
Thus 400 spheres are obtained by melting the solid cone.
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