What are the first and second Laws of Thermodynamics? 

Expert Answers

An illustration of the letter 'A' in a speech bubbles

The first Law of Thermodynamics concerns the state of matter and energy. According to this law, there is a specific and finite amount of matter and energy in the universe, and that amount cannot be increased or decreased; instead, all matter and energy can be changed in form to one...

Unlock
This Answer Now

Start your 48-hour free trial to unlock this answer and thousands more. Enjoy eNotes ad-free and cancel anytime.

Start your 48-Hour Free Trial

The first Law of Thermodynamics concerns the state of matter and energy. According to this law, there is a specific and finite amount of matter and energy in the universe, and that amount cannot be increased or decreased; instead, all matter and energy can be changed in form to one or the other, without ever losing the gross total of all matter/energy. Because of this, no system can ever put out more energy than it takes in, and no matter can ever be entirely destroyed.

The second Law of Thermodynamics concerns entropy, or the tendency for an isolated system to come to a stable state. Because the universe is a closed system, having a finite amount of matter/energy with no method of creating or destroying it, everything in the universe is moving towards a state of equilibrium, where all matter and energy are in the same physical state and the same temperature. This eventual fate is called the "Heat Death of the Universe," at which point there can be no motion because everything is in exactly the same state.

Approved by eNotes Editorial Team
An illustration of the letter 'A' in a speech bubbles

First Law ....(conservation of energy)

Energy can neither be created neither destroyed but can be transformed from one form to another form, the toatal energy in the universe remain constant

Example - work done by the mechanical force...

Second law of thermodynamics..

Explain you about the direction of heat transfer...

it is impossible to extract an amount of heat from a hot reservoir and use it all to do work. Some amount of heat must be exhausted to a cold reservoir.

Approved by eNotes Editorial Team
An illustration of the letter 'A' in a speech bubbles
First Law of thermodynamics: Energy is neither created nor destroyed it can only be transfered. This is the law of conservation of energy. While the energy is conserved, the internal energy f a system changes as the heat and work are transferedinthe system or out of the system.
 
Second Law of thermodynamics: Heat transfer. In any cyclic process the entropy will either increase or remain the same.
Approved by eNotes Editorial Team