Answer:
The temperature of cold reservoir should be 246.818 K for efficiency of 35%
Explanation:
In first case we have given efficiency of Carnot engine = 26 % = 0.26
Temperature of cold reservoir [tex]T_L=281K[/tex]
We know that efficiency of Carnot engine is given by
[tex]\eta =1-\frac{T_L}{T_H}[/tex]
[tex]0.26 =1-\frac{281}{T_H}[/tex]
[tex]T_H=379.72K[/tex]
For second Carnot engine efficiency is given as 35% = 0.35
And temperature of hot reservoir is same so [tex]T_H=379.72K[/tex]
So [tex]0.35=1-\frac{T_L}{379.72}[/tex]
[tex]T_L=246.818K[/tex]
So the temperature of cold reservoir should be 246.818 K for efficiency of 35%