{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Lecture 12

# Lecture 12 - Physics 040B/001-S08 Chap 17:1-7...

This preview shows pages 1–5. Sign up to view the full content.

May 13, 2008 Physics 40B Lecture 12 1 Physics 040B/001-S08 Chap. 17:1-7 Thermodynamics Review Standing Wave Patterns for Air Columns Pipe Open at Both Ends Displacement Anti-nodes Pressure Nodes (Atmospheric) Same as String f n = n v 2 L all n Open One End-Closed Other End f n = n v 4 L n odd Beats-Superposition of Two Waves with Different Frequencies f Beat = f 1 " f 2 " f = f v ± v L v m v S # \$ % ( Doppler Effect for Sound Waves

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

View Full Document
May 13, 2008 Physics 40B Lecture 12 2 Temperature and Thermodynamics Microscopic model: describe properties of individual molecules Macroscopic model: use thermodynamics variables (developed by von Helmhotz) Pressure P Temperature T Volume V # moles n Internal energy U Entropy S Use to deﬁne “state of system” without knowledge of details at microscopic level Equilibrium: variables don’t change with time Thermal equilibrium : two systems in contact will be at same temperature (eventually)
May 13, 2008 Physics 40B Lecture 12 3 Zeroth Law of Thermodynamics Two systems in thermal equilibrium (same temperature) with a third system are in thermal equilibrium (same temperature) with each other A B C After some time, all systems equilibrium (same temperature) Needed zeroth law after 1st law of thermodynamics was deﬁned Use zeroth law to measure temperature (Thermometry)

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

View Full Document
May 13, 2008 Physics 40B Lecture 12 4 Constant Volume Gas Thermometer Assume T proportional to p , measure p Calibrate at freezing (0 o Celsius) and boiling (100 o Celsius) points of water at 1 atmosphere of pressure Extrapolate back to p = 0, T = -273.15 C --Absolute Zero! CVG Thermometer
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 18

Lecture 12 - Physics 040B/001-S08 Chap 17:1-7...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online