The efficiency of a carnot engine is 50%. The temperature of the hot reservoir is kept constant. By what amount should the temperature of the cold reservoir be decreased so that efficiency becomes 60%.

The efficiency of a carnot engine is 50%. The temperature of the hot r

1.	The efficiency of a carnot engine is 50%. The temperature of the hot reservoir is kept constant. By what amount should the temperature of the cold reservoir be decreased so that efficiency becomes 60%.
A.	1K
B.	2K
C.	30K
D.	83K
Answer» B. 2K