Q. Water falls from a height of 500 m. What is the rise in temperature of water at the bottom if whole energy is used up in heating water?
A) 0.96$℃$
B) 1.02$℃$
C) 1.16$℃$
D) 0.23$℃$
Explanation
(c) Heat absorbed by water = Heat produced $mc\ \mathrm{\Delta}T = \frac{mgh}{J}$
$\mathrm{\Delta}\ T = \frac{gh}{Jc} = \ \frac{980 \times 500 \times 100}{4.2 \times 10^{7} \times 1\ } = \frac{900}{420} = 1.16℃$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.