Which of the following statement correctly describes heat? *
A Heat is the energy stored in a body at a certain temperature.
B Heat is the degree of hotness of a body.
C Heat is the energy transferred from high temperature to low temperature.
The correct answer and explanation is :
Correct Answer: C. Heat is the energy transferred from high temperature to low temperature.
Explanation:
Heat is a form of energy in transit. It is not the energy stored in a body or a measure of how hot an object is. Instead, heat is defined specifically as the energy that flows between two systems (or a system and its surroundings) due to a temperature difference. This energy always flows from a region of higher temperature to a region of lower temperature, and continues until thermal equilibrium is reached.
Let’s briefly examine the other choices:
- Option A: “Heat is the energy stored in a body at a certain temperature.”
This statement is incorrect because the energy stored in a body is called internal energy, not heat. Internal energy refers to the total kinetic and potential energy of the particles within the object. While internal energy can change due to heat transfer, it is not the same as heat itself. - Option B: “Heat is the degree of hotness of a body.”
This defines temperature, not heat. Temperature is a measure of the average kinetic energy of the particles in a substance and indicates how hot or cold an object is. Again, heat and temperature are related but distinct concepts. - Option C: “Heat is the energy transferred from high temperature to low temperature.”
This is the correct definition. Heat is energy in motion, resulting from a temperature difference. The units of heat are typically joules (J) in the SI system. Heat can be transferred through conduction, convection, or radiation depending on the medium and conditions.
In conclusion, heat should always be thought of as a process of energy transfer, not a stored quantity. This distinction is crucial in thermodynamics and helps explain a wide range of physical and chemical phenomena.