What is kinetic energy of each cubic meter of water in a stream that is moving with speed of$20\text{m/s}$ .

${\rho }_{water}={10}^3{\text{kgm}}^{-3}$

$\rho =\frac{\text{m}}{\text{v}}\text{;m}=\rho \text{V}={10}^3\times 1={10}^3\text{kg}$

velocity = ${\text{v = 20ms}}^{-1}$

$\therefore$ Kinetic energy$=\frac{1}{2}m{v}^2=\frac{1}{2}\times {10}^3\times 400=2\times {10}^5\text{J}$