Question

Water falls from a height of 50 m. Calculate the rise in the temperature of water when it strikes the bottom.
(g = 10 ms^-2; Specific heat capacity of water = 4200 J / kg°C)

Answer 1

If the whole of the energy due to the fall of water changes into heat energy, and 0°C be the rice in the temperature of water, then

mgh = ms θ°

Or m × 10 × 50 = m × 4200 × θ°

Or θ°, i.e. rise in temperature of water = `("m" xx 10 xx 50)/("m" xx 4200) = 5/42  ^circ "C"`

= 0.119 ° C = 0.12 ° C.