Question

The radi of the bases of two right circular metalic cones of same height 7 cm are 3.5 cm and 7 om. The cones are melted together and recasted into a solid sphere of radius R. Find R​

Answer 1

Answer:

Let h be the height of each cone. 

Then sum of the volumes of two cones =  Volume of the sphere

⇒31πr12h+31πr22h=34πR3

⇒ (r12+r22)h=4R3

⇒h=(r12+r22)4R3   [Hence proved]