A hollow sphere of internal and external radii 2 cm and 4 cm respectively is melted into a cone of base radius 4 cm. Find the height and slant height of the cone.
Volume of a sphere = (4/3)πr3
Volume of a cone = (1/3)πr2h
Given, radius of the internal and external surfaces of a hollow spherical shell are 2 cm and 4 cm respectively. It is melted into a cone of base radius 4 cm.
⇒ Volume of material in sphere = Volume of the cone
⇒ h = 14 cm
L2 = h2 + r2
⇒ l = √(142 + 42)
⇒ l =√212 = 14.56 cm
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