A Carnot engine, whose efficiency is 40 %, takes in heat from a source maintained at a temperature of 500 K. It is desired to have an engine of efficiency 60 %. Then, the intake temperature for the same exhaust (sink) temperature must be :

Question

A Carnot engine, whose efficiency is 40 %, takes in heat from a source maintained at a temperature of 500 K. It is desired to have an engine of efficiency 60 %. Then, the intake temperature for the same exhaust (sink) temperature must be : (A) efficiency of carnot engine cannot be made larger than 50 % (B) 1200 K (C) 750 K (D) 600 K

Tardigrade Admin · Accepted Answer

For 1st case efficiency -η=(1-(T1/T2))×100 (1-(T1/500))× 100=40 T1=300 K for 2nd case η=(1-(300/T2))× 100=60 T1=750 K

Q. A Carnot engine, whose efficiency is $40%$ , takes in heat from a source maintained at a temperature of $500 K$ . It is desired to have an engine of efficiency $60%$ . Then, the intake temperature for the same exhaust (sink) temperature must be :

efficiency of carnot engine cannot be made larger than $50%$

$1200 K$

$750 K$

$600 K$

For $1^{s t}$ case
efficiency $- η = (1 - \frac{T _{1}}{T _{2}}) \times 100 < b r / > (1 - \frac{T _{1}}{500}) \times 100 = 40$
$T_{1} = 300 K$
for $2^{n d}$ case
$η = (1 - \frac{300}{T _{2}}) \times 100 = 60$
$T_{1} = 750 K$

Q. A Carnot engine, whose efficiency is 40%, takes in heat from a source maintained at a temperature of 500K. It is desired to have an engine of efficiency 60%. Then, the intake temperature for the same exhaust (sink) temperature must be :

efficiency of carnot engine cannot be made larger than 50%

1200K

750K

600K