A pump of 200 W power is lifting 2kg water per second from an average depth of 10m. The velocity with which water comes out of the pump is, (Take g = 9.8 ms^–2) $\_\_\_\_\_\_$ × 10^–1 ms^–1

Given,

P = 200W

m= 2kg

h = 10m

water's exit rate from the pump in terms of velocity.

total energy,

$\mathrm{T}=\mathrm{mgh}+\frac{1}{2}{\mathrm{mv}}^2$

$\mathrm{Power} \mathrm{P}=\frac{\mathrm{T}}{\mathrm{time}}\Rightarrow 200=\frac{\mathrm{T}}{1}$

$\Rightarrow 200=\mathrm{mgh}+\frac{1}{2}{\mathrm{mv}}^2$

$\Rightarrow 200=2\times 10\times 9.8+\frac{1}{2}\times 2\times {\mathrm{v}}^2$

$\therefore \mathrm{v}=2\mathrm{m}/\mathrm{s}$

Hence the correct answer is 2m/s.