$A$ Carnot engine operating between temperatures $600 \,K$ and $300 \,K$ absorbs $800 \,J$ of heat from the source. The mechanical work done per cycle is (in $\,J$)

Two Carnot engines $A$ and $B$ are operated in series. The engine $A$ receives heat from the source at temperature $T_1$ and rejects the heat to the sink at temperature $T$. The second engine $B$ receives the heat at temperature $T$ and rejects to its sink at temperature $T_2$. For what value of $T$ are the efficiencies of the two engines equal?

$A$ Carnot engine has the same efficiency between $800 \ K$ to $500 \ K$ and $x \ K$ to $600 \ K$. The value of $x$ is ...... $K$. (in $K$)

$A$ Carnot engine with efficiency $50\,\%$ takes heat from a source at $600\,K$. In order to increase the efficiency to $70\,\%$,keeping the temperature of the sink the same,the new temperature of the source will be $.........\,K$.

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

$A$ Carnot heat engine absorbs $600 \ J$ of heat from a source at a temperature of $127^{\circ} C$ and rejects $400 \ J$ of heat to a sink in each cycle. The temperature of the sink is (in $K$)