Question

A solid piece of iron of dimensions $49$cm $\times$ $33$cm $\times$ $24$cm is moulded into a sphere. The radius of the sphere is __________.

• A. $21$cm
• B. $28$cm
• C. $35$cm
• D. None of these

Answer 1

The correct option is A $21$cm

Since, The piece is moulded into sphere material will remain conserved.

Therefore, Volume will remain Same.

$\therefore VolumeofSphere=Volumeofcuboid$

$⟹\frac{4}{3}\pi r^3=49\times 33\times 24.$

$⟹r^3=\frac{49\times 33\times 24\times 3\times 7}{4\times 22}$

$⟹r^3=49\times 3\times 3\times 3\times 7$

$⟹r=21cm$