Define thermodynamics & laws of thermodynamics

Thermodynamics:

  • Thermodynamics is a branch of physics that deals with the relationships between heat, work, and energy in a system. It studies the changes in energy that occur in a system and the laws that govern these changes. 
  • The field of thermodynamics is used to understand and predict the behavior of a wide range of physical and chemical systems, including engines, power plants, refrigeration systems, and many others.

THERMODYNAMICS LAWS


Laws of Thermodynamics:

  • The laws of thermodynamics are a set of fundamental principles that describe the behavior of energy and matter in a thermodynamic system. 
  • There are four laws of thermodynamics, which are:


First Law of Thermodynamics (Law of Conservation of Energy):

  • This law states that energy cannot be created or destroyed, only converted from one form to another. 
  • The total energy of a system remains constant, and the energy added to or removed from a system is equal to the change in the internal energy of the system. 
  • This means that the total amount of energy in the universe remains the same, and it can only be transformed from one form to another.


Second Law of Thermodynamics (Law of Entropy):

  •  This law states that the total entropy of a closed system will always increase over time, meaning that energy tends to flow from hotter to colder objects. 
  • This law also states that it is impossible for a heat engine to convert all of the heat it receives into useful work.
  • In simple terms, this law means that energy always flows from hotter to colder objects, and some energy is always lost in the process.


Third Law of Thermodynamics: 

  • This law states that as the temperature of a system approaches absolute zero, the entropy of the system approaches a minimum value. 
  • This means that as the temperature of a system gets closer to absolute zero, its entropy becomes closer to a minimum value and it becomes less and less likely for energy to flow from one part of the system to another.


Zeroth Law of Thermodynamics: 

  • This law states that if two systems are in thermal equilibrium with a third system, then they are in thermal equilibrium with each other. 
  • This law provides a way to define temperature and to determine the direction of heat flow in a system. 
  • It helps us to understand how temperature is defined and how heat flows between different objects.


These laws are important because they describe the behavior of energy and matter in a system, and they provide a framework for understanding and predicting the behavior of a wide range of physical and chemical systems. They are widely used in the design and analysis of energy systems, including engines, power plants, and refrigeration systems, as well as in the understanding of a wide range of physical and chemical phenomena.