Lecture - 1 (basics of thermodynamics)

It is a branch of science which deals with the energy interactions and its effect on system and surrounding.

Energy 

Energy can be understood as the ability to cause changes. 

System

It is a given mass or a region in space (control volume) Where our study is focused.
  • Closed systems are those systems in which energy interaction is there but mass interaction is not there.
  • Open systems are those systems in which both energy and mass interaction with surrounding is there.
  • Isolated systems or doors systems in which neither energy interaction takes place nor mass interaction takes place with surrounding.

Surrounding

Everything except the system is the surrounding. 
That part of the surrounding which is affected directly by the system is called immediate surroundings

Boundary

It is a real or imaginary surface which separates the system from the surroundings. Boundary can be fixed or movable.

Pressure in gasses

According to kinetic theory of gases the molecules of the gases are in random motion and due to this random motion they collide with the walls of container. The average normal force due to these collisions is termed as pressure. 
For video of this lecture check out my YouTube channel Mechanical education hub 

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