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Snezhnost [94]
3 years ago
12

A heat engine has a cold reservoir of 250°C and a hot reservoir of 715°C. What is the efficiency of the engine?

Physics
2 answers:
Margarita [4]3 years ago
6 0
If the heat engine is a perfect carnot cycle engine, then
efficiency = (T2-T1)/T2  
where T1=temperature of cold reservoir ( ° K) = 250+273.15 = 523.15
           T2=temperature of hot reservoir ( ° K)  = 715+273.15 = 988.15

Therefore
efficiency = (T2-T1)/T2 = (988.15-523.15)/988.15 = 0.4706 = 47% 

Note: this is the theoretical maximum efficiency of a perfect heat engine.  Real-life engines do not achieve this value.
Illusion [34]3 years ago
5 0

The answer is A. 65.0% for plato users, i got 100% on the test  :)

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calculate earths velocity of approach toward the sun when earth in its orbit is at an extremum of the latus rectum through the s
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Answer:

Hello your question is incomplete below is the complete question

Calculate Earths velocity of approach toward the sun when earth in its orbit is at an extremum of the latus rectum through the sun, Take the eccentricity of Earth's orbit to be 1/60 and its Semimajor axis to be 93,000,000

answer : V = 1.624* 10^-5 m/s

Explanation:

First we have to calculate the value of a

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input the given values into equation 1 above

r = 149.626 * 10^9 m

next calculate the Earths velocity of approach towards the sun using this equation

v^2 = \frac{4\pi^2 }{r_{c} }   ------ (2)

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equation 2 becomes

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