This question has Statement 1 and Statement 2. Of the four choice… - Vidyadip

MCQ

This question has Statement $1$ and Statement $2.$ Of the four choices given after the Statements, choose the one that best describes the two Statements.

Statement $1 :$ An inventor claims to have constructed an engine that has an efficiency of $30\%$ when operated between the boiling and freezing points of water. This is not possible.

Statement $2:$ The efficiency of a real engine is always less than the efficiency of a Carnot engine operating between the same two temperatures.

A
Statement $1$ is true, Statement $2$ is true,

Statement $2$ is not the correct explanation of Statement $1.$
B
Statement l is true, Statement 2 is false .
C
Statement $1$ is false, Statement $2$ is true.
✓
Statement $1$ is true, Statement $2$ is true,

Statement $2$ is the correct explanation of Statement $1.$

✓

Answer

Correct option: D.

Statement $1$ is true, Statement $2$ is true,

Statement $2$ is the correct explanation of Statement $1.$

d
According to Carnot's theorem $-$ no heat engine working between two given temperatures of source and sink can be more efficient than a perfectly reversible engine i.e. Carnot engine working between the same two temperatures.

Efficiency of Carnot's engine, $n=1-\frac{T_{2}}{T_{1}}$

$ where, T_{1}= temperature \,of\, source $

$T_{2}= temperature of \sin k$

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