A hollow metallic Sphere with external diameter8cm and internal diameter 4cm is melted and moulded into a cone having base diameter 8cm. The height of the cone is

Given: A hollow metallic Sphere with external diameter8cm and internal diameter 4cm


A cone having base diameter 8cm


Radius of the cone is: = 4cm


External Radius of the sphere is = 4cm


Internal Radius of the sphere is = 2cm


Volume of a Hollow Sphere is given by: π((r1)3 – (r2)3) (here r1 and r2 are External and internal radii of the hollow sphere respectively)


Let V1 be the Volume of the Hollow sphere.


V1 = π((r1)3 – (r2)3)


V1 = π((4)3 – (2)3) = π(64 – 8) = π(56)


Volume of the cone is given by × π × r2 × h


Let V2 be the volume of the cone


V2 = × π × r2 × h


V2 = × π × (4)2 × h


Here, Hollow sphere is melted and moulded into a cone.


V1 = V2


π(56) = × π × (8)2 × h


× π × 16 × h = × π × (56)


h = = 14cm


Height of the cone is 14cm

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