First Law of Thermodynamics

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First Law of Thermodynamics

Published by: Nuru

Published date: 26 Jun 2021

First Law of Thermodynamics in Grade 12

First Law of Thermodynamics

Thermodynamics is the branch of physics that deals with the relationships between heat and other forms of energy. “First Law of Thermodynamics says that the internal energy of a system has to be equal to the work that is being done on the system, plus or minus the heat that flows in or out of the system and any other work that is done on the system,” said Saibal Mitra, a professor of physics at Missouri State University. “So, it’s a restatement of conservation of energy.”

The first law of thermodynamics also known as the law of conservation of energy. It can be stated as the total amount of energy in the universe i.e. system and surrounding remains constant whatever one form of energy can be converted into another form.

  1. It is impossible to construct a perpetual motion machine i.e. A machine that would produce work continuously without consuming energy.
  2. There is an exact equivalent between heat and mechanical work. I.e. for every 4.184j of work.

 

Advantage of First Law of Thermodynamics

  • The total amount of energy in the universe system and surrounding remains constant.
  • When one form of energy disappears is convertible on the equivalent amount of another form energy appears.

Limitations or Drawn Backs of First Law of Thermodynamics:

  1. It does not explain why the extent and direction of convertibility of one form of energy into another form.
  2. it does not explain why the natural process is unidirectional.
  • It does not explain why the chemical reactions do not go to completion.
  1. It does not explain the feasibility of a chemical reaction i.e. whether the given reaction will accuse or not under given sets of conditions.
  2. It simply says the equivalent between heat and mechanical work but it has been found that all work can be converted into heat but all heat cannot be converted into without leaving the same permanent changes in the system or surrounding.