thermodynamic process at first we need to know what is process a process is nothing but a transformation from one state to another but in thermodynamics the transformation of a system from one equilibrium state to another is called a process now what is thermodynamic process when the thermodynamic system changes from one state to another the operation is called a thermodynamic process this process involves the change of conditions such as temperature pressure and volume for example consider a piston and cylinder arrangement in which four weights are placed on the piston if two of the weights are removed the piston rises and that changes the state of the system let p1 and v1 be the initial values of pressure and specific volume before removing the weight and p2 v2 are the corresponding values after the system has attained a new state in this process energy may be transferred from or into the system and can be done by or on the system types of thermodynamic process the various types of thermodynamic processes are isothermal process adiabatic process isochoric process isobaric process and cyclic process now let's discuss these processes in brief first one is isothermal process isothermal is derived from the greek words isos and therm iso means equal thermal describes the heat of a system so isothermal means equal heat this process is also known as constant temperature process an isothermal process is defined as one in which the temperature of the system remains constant during the change from its initial to final state for an isothermal process dt is equal to zero that means the initial and final temperature in this process is same for example the boiling of water at constant temperature as shown in the above picture the water is boiling but this process occurs at the constant temperature second one is adiabatic process the word adiabatic comes from the greek word adiabatos adiabatos means impossible this system can be considered to be perfectly insulated so adiabatic means occurring without loss or gain of heat adiabatic process is a no heat transfer process an adiabatic process is defined as one in which there is no exchange of heat between the system and surrounding during the process so this process can be considered to be perfectly insulated and energy is transferred only as work since there is no heat added or lost in this system then for adiabatic process dq is equal to zero here is a frictionless piston cylinder based enclosure the piston moves up and down that means expansion and compression takes place over here but there is no heat exchange occurring between this system and surrounding such as hot water in an ideal thermos plus because a thermos plus does not allow for the heat transfer to take place through its walls next one is isochoric process isochoric is derived from the greek words isos and quora iso means equal or constant coric means space or volume so isogoric means same space or volume it is also called constant volume or isovolumetric or isometric process an isochoric process is defined as the one in which the volume of the system remains constant during its change from initial to final state for an isochoric process initial volume is equal to final volume so db is equal to zero the boiling of water in a closed vessel is an example of isochoric process in this process the vessel is closed that means the volume of the vessel remains the same the volume is neither increasing nor decreasing isobaric process the word isobaric is derived from the greek words isos and baros iso means equal and baros means weight so isobaric means equal pressure or weight an isobaric process is defined as one in which the pressure of the system remains constant during its change from the initial to final state since the pressure is constant initial pressure is equal to final pressure so for an isobaric process dp is equal to zero for example the boiling of water in an open vessel the boiling of water takes place at atmospheric pressure only the pressure neither increases nor decreases last one is cyclic process it is also known as constant pressure process when a system returns to its original state after completing a series of changes then it is said that a cycle is completed this process is known as a cyclic process for cyclic process d e is equal to zero d h is equal to zero as in cyclic process the initial and the final state is same for cyclic process the net change in internal energy is zero the carnot cycle is best example of cyclic process because inside the carnot engine fuel burns and converts the heat energy into mechanical work now there are two more important processes one is reversible process and another one is irreversible process what is reversible process the process in which the system and surrounding can be restored to the initial state from the final state without producing any changes in the thermodynamic properties of the universe is called a reversible process melting of ice cream is a reversible process molten ice cream can be changed back to its solid form now what is irreversible process let's see what is irreversible process the process in which the system and surrounding cannot be restored to the initial state from the final stage is called an irreversible process a mixture of cement powder sand and water is an example of irreversible process this combination results in a hard solid and it cannot be reversed if you like this video please like and share and write down your thoughts and suggestions in the comment section please don't forget to subscribe to the channel thank you you