Laws of thermodynamics

• An open system includes the transfer and exchange of both matter and energy with the system's surroundings.
• Closed system - energy, in the form of light can enter.
• Isolated system - there is no interaction between the system and surroundings.
• Isolated system - There is no mass or energy transfer across the system boundary.
• system - the part where we focus our attention.
• System + surroundings = universe
• Surroundings - everything else in the universe.
• Boundary - imaginary line that separates the system from its surroundings.
• Types of systems:

  A) Open system

  B) Closed system

  C) Isolated system

  
• Types of walls:

  A) Diathermal walls

  B) Adiabatic walls

  
• To understand thermodynamics, it is necessary to describe the state of a system.
• Laws of thermodynamics:

  A) Zeroth law

  B) First law

  C) Second law

  D) Third law

  
• TRUE or FALSE

  Zeroth Law states that if two bodies are separately in thermal equilibrium with a third body, then they must be in thermal equilibrium with one another.

  TRUE
• The forgotten law of science

  Zeroth law
• In zeroth law, two systems are said to be in thermal equilibrium if there is no heat flow between them when they are brought into contact.
• Temperature - The indicator of thermal equilibrium in the sense that there is no net flow or heat between two systems in thermal contact that have the same temperature.
• TRUE or FALSE

  Energy can not be created nor destroyed

  TRUE
• Second law - applies the conservation of energy principle to systems where heat transfer and doing work are the methods of transferring energy into and out of the system.
• These type of walls permit heat flow.

  Diathermal walls
• These type of walls do not permit heat flow.

  Adiabatic walls
• Enumerate what the laws are about.

  A) Thermal equilibrium

  B) Internal energy

  C) State of a system

  D) Heat pumps

  E) Heat engine

  
• limitation of "first law" - states that a certain energy flow takes place when a system undergoes a process or change of state is possible or not.
• Which law gives more information about thermodynamics processes?

  Second law
• What law is used to determine the theoretical units for the the performance of mostly use of engineering systems like heat engines and heat pump.


  second law
• In the second law of thermodynamics, heat can flow itself from colder body to hotter body.
• A device that converts thermal energy into mechanical work.


  Heat engine
• A device that transfers heat energy from cold body to hot body.


  Heat pump
• Kelvin plank statement - it is impossible for any device as heat engine that operates on a cycle to receive heat from a single reservoir and produce net amount of work.
• In kelvin plank's statement, only part of the total heat absorbed by heat engine from a high temperature is converted to work, the remaining heat must be rejected at low temperature.
• TRUE or FALSE

  No heat engine has a 100% of thermal efficiency

  TRUE
• Clausius statement - "it is impossible to construct a device as heat pump that operates in a cycle and includes no effect other than the transfer of heat from lower temperature to higher temperature body"
• Clausius's statement means that heat cannot flow from cold body to hot body without any work input.
• Perpetual motion machine 2 (PMM 2)
• PMM 2 - If the engine heat only single thermal reservoir, in which heat is supplied is completely converted into an equivalent amount of work and its efficiency becomes 100%