Question

The diameter of the iron ball used for the shot -put game is 14 cm . It is melted and then a solid cylinder of height $2\frac{1}{3}$ cm is made . what will be the diameter of the base of the cylinder ?

• A. $14cm$
• B. $\frac{14}{3}$cm
• C. $28cm$
• D. $\frac{28}{3}$cm

Answer 1

The correct option is C $28cm$

Volume of sphere $=\frac{4}{3}\pi r^3$

$\Rightarrow r=7cm$

vol. of sphere $=\frac{4}{3}\pi (7{)}^3=\frac{1372\pi }{3}c{m}^3$ __(1)

vol of cylinder $=\pi R^{2}h$ __(2)

from eq (1) and (2)

$\frac{4}{3}\pi \left(7\right)\left(7\right)\left(7\right)=\pi \left(R\right)\left(R\right)\frac{7}{3}$

$R=14cm$

Diameter of cylinder $=28cm$