Question

team locomotives have an efficiency of 23.0% and operate with a hot steam temperature of 511°C. What would the cold reservoir temperature be if this were a Carnot engine?

What would the maximum efficiency of this steam engine be if its cold reservoir temperature were 155°C.

Answer 1

as given:

team locomotives have an efficiency of 23.0% so, = 23/100

and T1 = 511°C = 511+ 273 = 784 K and let T2 be the cold reservoir temperature be if this were a Carnot engine

so, we know efficiency = 1- T2/T1

or, 23/100 = 1 - T2/784

or, T2/784 = 1 - 23/100 = 77/100

or, T2 = 603.68 = 604 K (approx) ...................................ans

the maximum efficiency of this steam engine be if its cold reservoir temperature were 155°C ie, (155+273) = 428K

  1 = 1 - T2/T1 = 1 - 428/784 = 0.4541

= 45.41 % ..............................................................ANS