How many degrees does the water heat up, falling from a height of 15 m, if 30%

How many degrees does the water heat up, falling from a height of 15 m, if 30% of the work done in this case goes to heating the water?

Data: h (height of water fall) = 15 m; η (percentage of work done that goes to heating water) = 30% (0.3).

Reference values: g (acceleration due to gravity) = 9.81 m / s2; С (specific heat capacity of water) = 4200 J / (kg * ºС).

The change in water temperature when falling is determined from the equality: η * A = Q; η * m * g * h = C * m * Δt; η * g * h = C * Δt and Δt = η * g * h / С.

Let’s make a calculation: Δt = 0.3 * 9.81 * 15/4200 = 0.01 ºС.

Answer: Falling from a height of 15 m, the water can heat up by 0.01 ºС.