By: charnwit kheanpanya
Thermodynamics is a branch of physics which deals with the energy and study in effect of heat,work and energy on system
Laws of thermodynamics.
Zeroth laws : if two system are in thermal equilibrium with a third system,they must be in thermal equilibrium with each other.
such as if system A and system B are thermal equilibrium and system B and system C are thermal equilibrium. Also system A and system C are thermal equilibrium
First laws: Is often called Low of conservation of energy.That energy can be neither created nor destroyed.That impossible a machine violate the first low.Because flow of thermal energy from one object to another.
The difference of internal energy of a closed system is equal to the difference of the heat supplied to the system and the work done by it : ΔU = Q - W
Second laws:The entropy of any isolated system cannot decrease. Heat cannot be transfer from a colder to a hotter body. A result of energy transfer must have one direction, and all natural processes are irreversible.
Third law : if a system approaches absolute zero the entropy of the system approaches a minimum value.The third law of thermodynamics is a statistical law of nature regarding entropy and the impossibility of reaching absolute zero of temperature. This law provides an absolute reference point for the determination of entropy. The entropy determined relative to this point is the absolute entropy. Alternate definitions are, "the entropy of all systems and of all states of a system is smallest at absolute zero," or equivalently "it is impossible to reach the absolute zero of temperature by any finite number of processes".
Absolute zero is −273.15 °C (degrees Celsius), or −459.67 °F (degrees Fahrenheit) or 0 K (kelvin).
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