$A$ Carnot engine operates between $627^{\circ}C$ and $227^{\circ}C$. The efficiency of the Carnot engine is ....... $\%$

$Assertion :$ The Carnot cycle is useful in understanding the performance of heat engines.
$Reason :$ The Carnot cycle provides a way of determining the maximum possible efficiency achievable with reservoirs of given temperatures.

Consider a Carnot cycle operating between $T_1 = 500\,K$ and $T_2 = 300\,K$ producing $1\,kJ$ of mechanical work per cycle. Find the heat transferred to the engine by the reservoir at $T_1$ in Joules.

An engine operating between temperatures $T_1$ and $T_2$ has efficiency $\eta = \frac{1}{5}$. When $T_2$ is lowered by $45 \ K$,its efficiency becomes $\eta' = \frac{1}{2}$. Temperatures $T_1$ and $T_2$ are respectively:

For which of the following options will the efficiency of a Carnot engine be the highest?

$A$ scientist claims that their heat engine has an efficiency of $26\%$ when operating between a source temperature of $127^{\circ}C$ and a sink temperature of $27^{\circ}C$. This implies that: