Q. Two friends $A$ and $B$ are waiting for another friend for tea. $A$ took the tea in a cup and mixed the cold milk and then waits. $B$ took the tea in the cup and then mixed the cold milk when the friend comes. Then the tea will be hotter in the cup of

A) $A$
B) $B$
C) Tea will be equally hot in both cups
D) Friend’s cup
Explanation

(a) The rate of heat loss is proportional to the difference in temperature. The difference of temperature between the tea in cup $A$ and the surrounding is reduced, so it loses less heat. The tea in cup $B$ loses more heat because of large temperature difference. Hence the tea in cup $A$ will be hotter

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.