Q.
In a hydroelectric power station, the water is flowing at 2ms−1 in the river, which is 100m wide and 5m deep. The maximum power output from the river is
Given, area of river, A=100m×5m =500m2
Density of water, ρ=103kg/m3 and v=2ms−1 ∴ Mass of water flowing per second, m=Aρv =500×103×2=106kg/s
Power of power station, P= Kinetic energy of water flowing per second =21mv2=21×106×22 =2×106W=2MW