A 20% efficient real engine is used to speed up a train from rest to 5.00 m/s. It is known that an ideal (Carnot) engine using the same cold and hot reservoirs would accelerate the same train from rest to a speed of 6.50 m/s using the same amount of fuel. The engines use air at 300 K as a cold reservoir. Find the Temperature of the steam serving as the hot reservoir.
I know the efficiency of Carnot engine is 1- (T_c/T_h) and the thermal efficiency of a heat engine is 1- (Q_c/Q_h). I'm not sure how to set this up. Can you help?© BrainMass Inc. brainmass.com October 24, 2018, 6:13 pm ad1c9bdddf
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The solution includes detailed explanations and step-by-step calculations for finding the temperature of steam in a steam engine in a train.
Calculating Efficiency and Power in a Carnot Engine
A Carnot engine is used in a nuclear power plant. It receives 1500 MW by heat transfer with a source at 340C, and it rejects thermal waste to a nearby river at 27C. The river temperature rises by 3C. Determine the:
(i) Efficiency of the power plant
(ii) Power output of the power plant.