Question

Find the mass of the object, which is in the form of a sphere of radius √5cm, centred at the origin. The density at any point is given to be constant 2.

Answer 1

Mass of the object $m$ could be found by multiplying volume $V$ by density $\rho$.

$V=\frac{4}{3}\pi r^3 = \frac{4}{3}\pi 5^{\frac{3}{2}}$ - volume of sphere

$m = V\rho=\frac{4}{3}\pi 5^{\frac{3}{2}}*2 = \frac{8}{3}\pi 5^{\frac{3}{2}}$