The surface area of a solid metallic sphere is 616 cm2. It is melted and recast into a solid cone of height 28 cm. Find the diameter of the base of the cone so formed. (Take π = 22/7)
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 14 cm.
According to the question,
The surface area of the sphere = 616
616 = 4πr2
616 = 4 × (22/7) r2
r = 7cm
Volume of the sphere = Volume of the cone
(4/3)πr3 = (1/3)πR2h
4 × 7 × 7 × 7 = R2 × 28
R = 7 cm
Radius of the cone = 7 cm
So, the diameter of the cone = 7 × 2 = 14cm