A metallic sphere of radius 4.2 cm is melted and recast into the shape of a cylinder of radius 6 cm. Find the height of the cylinder
Radius (r1) of hemisphere = 4.2 cm
Radius (r2) of cylinder = 6 cm
Let the height of the cylinder be h.
The object formed by recasting the hemisphere will be the same in volume.
Volume of sphere = Volume of cylinder
πr13 = πr22h
π (4.2)3 = π (6)2h
* 
= h
h = (1.4)3
= 2.74 cm
Hence, the height of the cylinder = 2.74 cm
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