Question

The efficiency of any engine is always (a)less than 1 (b) one (c)more than one( D )all of these

Answer 1

Answer:

Given :

An engine has been provided.

To find:

The value of range of efficiency of that engine.

Concept:

Efficiency of an engine refers to the delivery of work with respect to the amount of Heat supplied from the source.

It is denoted as η.

Let sink temperature be T1 , source temperature be T2

$\boxed{ \huge{ \red{ \eta = 1 - \frac{T1}{T2}}}}$

Now , conventionally sink temperature is always less than that of source temperature.

In that case , T1/T2 is a proper fraction.

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \boxed{ \huge{ \red{ \frac{T1}{T2} < 1}}}$

Hence , if we do subtraction of that value from 1 , it's obvious that value of η will be less than one.

This is the mathematical proof.

Logical Proof:

Any thermodynamic machine will never be able to convert 100% supplied energy to work. This is because , it always loses. some quantity of energy to the surroundings.

So final answer :

$\boxed{ \huge{ \blue{option \: a)}}}$