Question

How many lead balls each of radius $1$ cm can be made from a sphere whose radius is $8$ cm?

• A. $312$
• B. $412$
• C. $512$
• D. $612$

Answer 1

The correct option is C $512$

In the given sphere
radius=8 cm
$V_{1}Volumeofthesphere=\frac{4}{3}\pi r^3$
$=\frac{4}{3}\pi {\left(8\right)}^3=\frac{2048}{3}\pi cu.cm$
In the given ball
radius = 1 cm.
$V_2=Volumeoftheball=\frac{4}{3}\pi r^3=\frac{4}{3}\pi {\left(1\right)}^3=\frac{4}{3}\pi cu.cm$
Number of balls$\frac{V_1}{V_2}=\frac{204}{3}\times \frac{3}{4\pi }=512balls$