Question

A shot-putt is a metallic sphere of radius 4.9 cm. If the density of the metal is 7.8 gm/cm3. Find the mass of the shot-putt.

Answer 1

radius, r= 4.9 cm
$$\begin{gathered} Volume=\frac{4}{3}\pi r^3=\frac{4}{3}*\frac{22}{7}*4.9^3=493c{m}^3; \\ Density=\frac{mass}{volume}; \\ 7.8=\frac{mass}{493} \\ mass=493*7.8=3845.4gm \end{gathered}$$