Ch 20: The First Law of ThermodynamicsSee all chapters
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Ch 01: Units & Vectors
Ch 02: 1D Motion (Kinematics)
Ch 03: 2D Motion (Projectile Motion)
Ch 04: Intro to Forces (Dynamics)
Ch 05: Friction, Inclines, Systems
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Ch 20: The First Law of Thermodynamics
Ch 21: The Second Law of Thermodynamics
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Ch 37: Nuclear Physics
Ch 38: Quantum Mechanics

First Law of Thermodynamics

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Sections
Internal Energy
Introduction to Heat Capacity
First Law of Thermodynamics
Intro to Thermal Processes
Work & PV Diagrams

Solution: Six moles of a monatomic ideal gas undergo the process shown in the figure. State 1 has pressure p1 = 4.00 x 105 Pa and volume V1 = 2.00 x 10-3 m3. State 2 has pressure p2 = 3.00 x 105 Pa and volume V2 = 6.00 x 10-3 m3.  a) In this process, what is ΔU, the change in the internal energy of the gas? b) What is the heat flow Q for this process?  c) Does heat flow into the gas or out of the gas?      

Problem

Six moles of a monatomic ideal gas undergo the process shown in the figure. State 1 has pressure p= 4.00 x 105 Pa and volume V1 = 2.00 x 10-3 m3. State 2 has pressure p= 3.00 x 105 Pa and volume V2 = 6.00 x 10-3 m3

a) In this process, what is ΔU, the change in the internal energy of the gas?

b) What is the heat flow Q for this process? 

c) Does heat flow into the gas or out of the gas?