# Best answer: Why is it impossible to design a 100% efficient heat engine?

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## Can you design an engine of 100% efficiency?

It is impossible for heat engines to achieve 100% thermal efficiency () according to the Second law of thermodynamics. This is impossible because some waste heat is always produced produced in a heat engine, shown in Figure 1 by the term.

## Why is it impossible to build a heat engine with 100% efficiency?

The efficiency of a heat engine can be 100% only if all the heat energy gets converted into work (or mechanical energy). … Since heat energy can never be transformed completely into mechanical energy, so the efficiency of a heat engine can never be 100 per cent.

## Why is a perfect heat engine Impossible?

It is impossible to construct a perfect heat engine. … Since it absorbs heat, its entropy is increased. If it increases its entropy enough, it will ensure that the entire system has a net increase in entropy.

## Why is it that no engine can be 100% efficient What law states this?

We know from the second law of thermodynamics that a heat engine cannot be 100 percent efficient, since there must always be some heat transfer Qc to the environment. … This increases heat transfer Qc to the environment and reduces the efficiency of the engine. Obviously, then, reversible processes are superior.

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## Why is Carnot engine Impossible?

No engine has been built using the cycle named in honor of Carnot because two parts of the cycle require total insulation. And two require conduction with one of either the hot or the cold sinks.

## What is the heat engine not 100% efficient?

A heat engine is considered to be 100% efficient if only all the heat is converted into useful work or mechanical energy. Since heat engines cannot convert all the heat energy into mechanical energy, their efficiency can never be 100%.

## How can we increase the efficiency of a heat engine can we get 100% efficiency if yes how?

Answer: 100 % energy efficiency is never possible as there would be always some losses in the form of heat, friction, hysteresis, eddy losses etc.

## Is a perfect engine possible?

While Carnot engines are ideal engines, in reality, no engine achieves Carnot’s theoretical maximum efficiency, since dissipative processes, such as friction, play a role. Carnot cycles without heat loss may be possible at absolute zero, but this has never been seen in nature.

## Is Carnot engine 100 efficient?

In order to achieve 100% efficiency (η=1), Q2 must be equal to 0 which means that all the heat form the source is converted to work. The temperature of sink means a negative temperature on the absolute scale at which the temperature is greater than unity.

## Are reversible processes 100% efficient?

Reversible processes are idealized situations of 100% efficiency, where we get maximum work for our effort and waste no energy. No real process is actually reversible, which is one aspect of the 2nd Law of Thermodynamics – some energy is always wasted.

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## What is the 2nd law of thermodynamics in simple terms?

The second law of thermodynamics means hot things always cool unless you do something to stop them. It expresses a fundamental and simple truth about the universe: that disorder, characterised as a quantity known as entropy, always increases.

## Is irreversible engines have maximum efficiency?

All the reversible and irreversible engines have the same efficiency. Irreversible engines have maximum efficiency. All engines are designed as reversible in order to obtain maximum efficiency.