h = average height of Niagara falls = 45 m
P = power generated by Stations I and II together = 1926 MW = 1926 x 10⁶ Watt
m = mass of water required to go over the falls
g = acceleration due to gravity
t = time = 1 sec
Power generated is given as
Power generated = potential energy lost/time
P = mgh/t
1926 x 10⁶ = m (9.8) (45)/1
m = 1926 x 10⁶ /(9.8 x 45)
m = 4.4 x 10⁶ kg
it is given that , 1 kg = 1 litre
hence
hence Volume of water = V = 4.4 x 10⁶ litre
