Question

A cylindrical rod whose height is 8 times of its radius is melted and recast into spherical balls of same radius. The number of balls will be

(a) 4

(b) 3

(c) 6

(d) 8

Answer 1

In the given problem, we have a cylindrical rod of the given dimensions:

Radius of the base (r_c) = x units

Height of the cylinder (h) = 8x units

So, the volume of the cylinder (V_c) =

Now, this cylinder is remolded into spherical balls of same radius. So let us take the number of balls be y.

Total volume of y spheres (V_s) =

So, the volume of the cylinder will be equal to the total volume of y number of balls.

We get,

Therefore, the number of balls that will be made is. So, the correct option is (c)