A metallic spherical shell of internal and external diameters 4 cm and 8 cm, respectively is melted and recast into the form a cone of base diameter 8 cm. The height of the cone is


Volume of spherical shell = Volume of cone recast by melting [1]


For Spherical Shell,


Internal diameter, d1 = 4 cm


Internal radius, r1 = 2 cm


[ as radius = 1/2 diameter]


External diameter, d2 = 8 cm


External radius, r2 = 4 cm


Now,


As volume of spherical shell


where r1 and r2 are internal and external radii respectively.


volume of given shell




Using [1] we have


Volume of cone = 224π /3 cm3


For cone,


Base diameter = 8 cm


Base radius, r = 4 cm


[ as radius = 1/2 diameter]


Let Height of cone be 'h'.


As,


volume of cone =


where r = Base radius and h = height of cone


Volume of given cone



16h = 224


h = 14 cm


So, Height of cone is 14 cm.

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