Question

Choose the correct option.

Water falls from a hight of 200 m. What is the difference in temperature between the water at the top and bottom of a waterfall given that the specific heat of water is 4200 J kg^-1 °C-1?

Options

• 0.96° C

• 1.02° C

• 0.46° C

• 1.16° C

Answer 1

0.46° C

Explanation:

The potential energy at height = kinetic energy at bottom Assuming all kinetic energy is converted into heat, Let ΔT be the rise in temperature of water observed at the bottom 

∴ mgh = m s ΔT

∴ ΔT = `"gh"/"s" = (9.8 xx 200)/4200 = 0.467^circ`C