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Chapter 12 Temperature, Heat and the 1st law of thermodynamics
12. 1 Temperature
The concept of temperature has evolved from the common concepts of hot and cold. Our human
perception of what feels hot or cold is a relative one.
Temperature is operationally defined to be what we measured with a thermometer.
Temperature scales
The Kelvin scale is an absolute temperature scale defined to have 0 K at the lowest possible temperature,
called absolute zero.
Celsius
Fahrenheit
The curvature of a bimetallic strip depends on temperature.
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Thermal equilibrium and the zeroth law of thermodynamics
Taken from Halliday
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Uniform circular motion: motion in a circular path at constant speed.
8.1 Rotation Angle and Angular Velocity
Taken from Halliday
12.2 Thermal expansion
Area Expansion
Volume Expansion
Why?
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Measuring temperature
Taken from Halliday
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Heat and Temperature
The transferred energy is called heat and symbolized Q.
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Taken from Halliday
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Relating the linear and angular variables
Molar Specific Heat
Heats of transformation
Work
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The 1st law of Thermodynamics
The tangential component of the linear acceleration of the point
8.2 Centripetal acceleration
Thermodynamic processes
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Special cases for the 1st law of thermodynamics
Taking the ratio of BC to BA in each triangle, we obtain
v  v1  v2
v r

v
r
v 
v
r
r
v v r

t r t
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Heat Transfer Mechanisms
Conduction
8.3 Centripetal force
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A Composite slab
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Taken from Halliday
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Taken from Halliday
Exercises: 12.1, 12.18
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Chapter 13 The kinetic theory of gas
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C
Collisions between molecules and the wall
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90
91
92
93
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Internal energy
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f: the degree of freedom
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Proof
Taken from Halliday
Exercises: 13.14, 13.46