Question

How many spheres of iron having radius $1cm$ can be made by melting a sphere of iron having $8cm$ radius?

• A. $64$
• B. $128$
• C. $356$
• D. $512$

Answer 1

Answer: (D)

$512$

$n=\frac{\frac{4}{3}\pi R^3}{\frac{4}{3}\pi r^3}$
$n=\frac{R^3}{r^3}=\frac{{\left(8\right)}^3}{{\left(1\right)}^3}\Rightarrow n=512$