Question

Water falls from a height of 100 m. Calculate the rise in temperature of water when it strikes the bottom. Given, S${}_w$​ = 4200 Jkg${}^{-1}$​${}^0$​C${}^{-1}$​ and g = 10 m/s${}^2$​.

• A. 0.273°C
• B. 0.360°C
• C. 0.238°C
• D. 1.258°C

Answer 1

The correct option is C

0.238°C

The potential energy of water is used to raise its temperature.

So, m g h $=mc\Delta T$

$\Rightarrow$ $\Delta$ T = $\frac{gh}{c}$ = $\frac{(10\times 100)}{4200}$ = 0.238 ${}^{\circ }$C