# chapter12 - Chapter 12 The Laws of Thermodynamics...

This preview shows pages 1–12. Sign up to view the full content.

The Laws of Thermodynamics The Laws of Thermodynamics Chapter 12 Chapter 12

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Principles of Thermodynamics Principles of Thermodynamics Energy is conserved FIRST LAW OF THERMODYNAMICS Examples: Engines (Internal -> Mechanical) Friction (Mechanical -> Internal) All processes must increase entropy SECOND LAW OF THERMODYNAMICS Entropy is measure of disorder Engines can not be 100% efficient
U = Q - P D V Converting Internal Energy to Mechanical Converting Internal Energy to Mechanical Work done by expansion W = Φ ξ , Φ = ΠΑ , ∆ ξ = ∆ ς / Α W = Π ς

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Example 12.1 Example 12.1 A cylinder of radius 5 cm is kept at pressure with a piston of mass 75 kg. a) What is the pressure inside the cylinder? b) If the gas expands such that the cylinder rises 12.0 cm, what work was done by the gas? c) What amount of the work went into changing the gravitational PE of the piston? d) Where did the rest of the work go? 1.950x10 5 Pa 183.8 J 88.3 J Compressing the outside air
Example 12.2a Example 12.2a A massive copper piston traps an ideal gas as shown to the right. The piston is allowed to freely slide up and down and equilibrate with the outside air. The pressure inside the cylinder is _________ the pressure outside. a) Greater than b) Less than c) Equal to

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Example 12.2b Example 12.2b A massive copper piston traps an ideal gas as shown to the right. The piston is allowed to freely slide up and down and equilibrate with the outside air. The temperature inside the cylinder is __________ the temperature outside. a) Greater than b) Less than c) Equal to
Example 12.2c Example 12.2c A massive copper piston traps an ideal gas as shown to the right. The piston is allowed to freely slide up and down and equilibrate with the outside air. If the gas is heated by a steady flame, and the piston rises to a new equilibrium position, the new pressure will be _________ than the previous pressure. a) Greater than b) Less than c) Equal to

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Some Vocabulary Some Vocabulary Isobaric P = constant Isovolumetric V = constant Isothermal T = constant Adiabatic Q = 0 V V V V P P P P
A massive piston traps an amount of Helium gas as shown. The piston freely slides up and down. The system initially equilibrates at room temperature (a) Weight is slowly added to the piston, isothermally compressing the gas to half its original volume (b) P is _______ P Outside Air: Room T, Atm. P Example 12.3a Example 12.3a a) Greater than b) Less than c) Equal to U = Q - P D V W = P D V

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
A massive piston traps an amount of Helium gas as shown. The piston freely slides up and down. The system initially equilibrates at room temperature (a) Weight is slowly added to the piston, isothermally compressing the gas to half its original volume (b) T is ________ T Outside Air: Room T, Atm. P Example 12.3b Example 12.3b a) Greater than b) Less than c) Equal to U = Q - P D V W = P D V
A massive piston traps an amount of Helium gas as shown. The piston freely slides up and down.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern