Laws of Thermodynamics Video Lecture | Physics for JEE Main & Advanced

Ans. The fundamental laws of thermodynamics are the laws that govern the behavior of energy in a system. There are four laws of thermodynamics: 1. The Zeroth Law of Thermodynamics states that if two systems are in thermal equilibrium with a third system, then they are in thermal equilibrium with each other. 2. The First Law of Thermodynamics, also known as the Law of Energy Conservation, states that energy cannot be created or destroyed, only transferred or transformed. 3. The Second Law of Thermodynamics states that in any energy transfer or transformation, the total entropy of a closed system will always increase over time. 4. The Third Law of Thermodynamics states that as the temperature of a system approaches absolute zero, the entropy of the system approaches a minimum value.

Ans. The first law of thermodynamics, also known as the Law of Energy Conservation, states that energy cannot be created or destroyed, only transferred or transformed. This law implies that the total energy of a closed system remains constant. In other words, the energy input to a system is equal to the energy output plus any energy stored within the system. It establishes the principle of energy conservation and provides a foundation for understanding the flow and transformation of energy in various processes.

Ans. Entropy is a measure of the disorder or randomness in a system. It is a thermodynamic property that quantifies the distribution of energy within a system. The second law of thermodynamics states that in any energy transfer or transformation, the total entropy of a closed system will always increase over time. This means that natural processes tend to move towards a state of higher entropy or greater disorder. The concept of entropy helps us understand why certain processes are irreversible and why there are limits to the efficiency of energy conversion.

Ans. The third law of thermodynamics states that as the temperature of a system approaches absolute zero (0 Kelvin or -273.15 degrees Celsius), the entropy of the system approaches a minimum value. At absolute zero, a perfectly ordered crystalline substance would have zero entropy. However, achieving absolute zero is theoretically impossible. The third law of thermodynamics provides insights into the behavior of systems at extremely low temperatures and helps establish the relationship between temperature, entropy, and the limits of achieving absolute zero.

Ans. The Zeroth Law of Thermodynamics is important in establishing thermal equilibrium because it defines the concept of temperature and allows us to compare the temperatures of different systems. The law states that if two systems are in thermal equilibrium with a third system, then they are in thermal equilibrium with each other. This means that if two systems have the same temperature as a third system, they have the same temperature as each other. The Zeroth Law provides a basis for measuring temperature and enables the formulation of temperature scales, such as the Celsius and Kelvin scales, which are crucial in understanding heat transfer and thermal equilibrium.