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प्रश्न
A solid metallic cylinder has a radius of 2 cm and is 45 cm tall. Find the number of metallic spheres of diameter 6 cm that can be made by recasting this cylinder .
उत्तर
Radius of the solid cylinder (r) = 2 cm
Height of cylinder (h) = 45 cm
Volume of cylinder = `pir^2h`
= `22/7 xx 2 xx 2 xx 45`
= `3960/7` cm3
Diameter of metallic sphere = 6 cm
Therefore, Radius (r1) = 3 cm
Volume of sphere = `4/3pi(r1)^3`
= `4/3 xx 22/7 xx 3 xx 3 xx 3`
= `792/7`cm3
Therefore, No. of spheres = `3960/7 + 792/7 = 5`
Number of spheres that can be made = 5
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