## Thermodynamics B/C

WhatScience?
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### Thermodynamics B/C

Welcome to 2018 Thermodynamics!

A heat engine has a thermal efficiency of 45%. How much power does the engine produce when heat is transferred into it at 10^9 kJ/Hr?

"When you clean your room, you are increasing the total chaos of the universe" - Hank Green Crash Course (Entropy)

Events 2018

Thermodynamics, Potions and Poisons, Disease Detectives, Optics, and Towers

daydreamer0023
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### Re: Thermodynamics B/C

Welcome to 2018 Thermodynamics!

A heat engine has a thermal efficiency of 45%. How much power does the engine produce when heat is transferred into it at 10^9 kJ/Hr?

Is this correct?
"I am among those who think that science has great beauty. A scientist in his laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale." - Marie Curie

WhatScience?
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Posts: 394
Joined: July 16th, 2017, 4:03 pm
Division: C
State: NJ

### Re: Thermodynamics B/C

Welcome to 2018 Thermodynamics!

A heat engine has a thermal efficiency of 45%. How much power does the engine produce when heat is transferred into it at 10^9 kJ/Hr?

Is this correct?
No, but close
"When you clean your room, you are increasing the total chaos of the universe" - Hank Green Crash Course (Entropy)

Events 2018

Thermodynamics, Potions and Poisons, Disease Detectives, Optics, and Towers

daydreamer0023
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Posts: 195
Joined: January 29th, 2015, 5:44 pm
State: -
Location: I have no idea where I am, but I can tell you exactly how fast I'm going ;)

### Re: Thermodynamics B/C

Probably missed a decimal place on my part somewhere down the line in calculations...oh well. Next question:

How do state variables differ from path functions? Give two thermodynamics related example of each.
"I am among those who think that science has great beauty. A scientist in his laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale." - Marie Curie

WhatScience?
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Posts: 394
Joined: July 16th, 2017, 4:03 pm
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### Re: Thermodynamics B/C

"When you clean your room, you are increasing the total chaos of the universe" - Hank Green Crash Course (Entropy)

Events 2018

Thermodynamics, Potions and Poisons, Disease Detectives, Optics, and Towers

daydreamer0023
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Posts: 195
Joined: January 29th, 2015, 5:44 pm
State: -
Location: I have no idea where I am, but I can tell you exactly how fast I'm going ;)

### Re: Thermodynamics B/C

Looks correct to me. Your turn.
"I am among those who think that science has great beauty. A scientist in his laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale." - Marie Curie

WhatScience?
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Posts: 394
Joined: July 16th, 2017, 4:03 pm
Division: C
State: NJ

### Re: Thermodynamics B/C

A person wants to replace the window on their house, but they don't want their heating and cooling bills to change. The original window on the wall of the house has area A, thickness d, and is made out of glass that has a thermal conduction constant k. Which one of the following changes could be made to the window that would leave the rate of thermal conduction the same as the original window?

A: double the area, cut the thickness in half, cut the k constant in half

B: cut the area in half, cut the thickness in half, and double the k constant

C: quadruple the area, double the thickness, cut the k constant in half

D: double the area, double the thickness, quadruple the k constant
"When you clean your room, you are increasing the total chaos of the universe" - Hank Green Crash Course (Entropy)

Events 2018

Thermodynamics, Potions and Poisons, Disease Detectives, Optics, and Towers