Question

A man would feel iron and wooden balls equally cold or hot at:
A) $98.6^\circ C$
B) $98.6^\circ F$
C) $198.6^\circ F$
D) $198.6^\circ C$

Answer 1

Hint: In this question we have to find the temperature at which a man would feel iron and wooden equally cold or hot at.

Complete answer:
The man would feel iron and wooden balls equally hot or cold at a temperature when the heat flowing out of the system and heat flowing into the system is equal. In the given condition, the man has to feel equal hot or cold. So there should be an equal temperature difference between the man and object.
For this to happen there should be equal heat flow or there should be no heat flow. Only this condition in the given condition in the question will be fulfilled. The temperature of the body of man is $98.6^\circ F$, so the temperature of the object will also be $98.6^\circ F$. Only then the man will feel iron and wooden balls equally hot or cold.
Hence, from the above explanation we can see that $98.6^\circ F$ is the temperature at which a man would feel iron and wood equally cold or hot at.

Hence, Option B is the right answer.

Note: In these types of questions flow of heat is happening, so the first law of thermodynamics that the energy is always conserved, energy cannot be created or destroyed. It can only be transferred from one body to another. The Calorimeter law that heat transfers from hotter body to colder body, it also must be known. As we have seen that when there is no temperature difference there will not be any heat transfer. Such information should be in mind to solve these problems.