A solid cone of radius 5cm and height 12 cm is melted and recast into 150 hemispheres of radius 1 cm. Find the increase in surface area on recasting in terms of pi
Answers
Answered by
0
The increase in the surface area on recasting in terms of π = 360π .
r - radius of the solid cone = 5 cm
h - height of the cone = 12 cm
l - slant height of the cone = √(169) = 13 cm
Surface area of the solid cone = πr² + πrl
= 25π + 65π
= 90π cm²
The cone is melted and recast into 150 small hemispheres of radius 1 cm.
Surface area of hemisphere = 3π cm²
Total surface area of 150 hemispheres = 150 × 3π
= 450π cm²
Increase in the surface area = 450π - 90π = 360π
Similar questions