Niagara Falls Calculation?

[labelapark]

The water going over the Niagara Falls drops 70 meters to the river below. Assuming that all of the energy goes into heating the water, find the temperature rise of the water.

[Shawn A]

Use a 1 g basis:

1 g falling 70 meters gains:

g*h = 0.686 joules of energy

Divide this by the heat capacity (at 25 ºC is 4.184 Joules/g ºC),

is about 0.16 ºC

Not much, eh?