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Physics 170 - MechanicsLecture 37

Temperature and Kinetic theory

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Temperature and Heat

Temperature is a measure of relative hotness or coldness.Heat is the net energy transferred from one object to another due to a temperature difference.This energy may contribute to the total internal energy of the object, or it may do work, or both.

Temperature and Heat

When heat is transferred from one object to another, they are said to be in thermal contact.Two objects in thermal contact without heat transfer are in thermal equilibrium.

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:

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N (Number of particles) = n (number of moles) NA (Avogadro’s number)

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Kinetic Theory of Gases

According to the kinetic theory of gases, pressure is due to elastic collisions of molecules with container walls.

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=(2 x 3.2 x10-20 J)/(3x1.38x10-23 J/K)

Kinetic Theory of Gases

The internal energy of a monatomic gas is due to the kinetic energy of its atoms, and is therefore related to its temperature.

Summary

Celsius–Fahrenheit conversions:

Heat is the energy transferred from one object to another due to temperature difference.

SummaryIdeal gas law:

Absolute zero is –273.15°C.Celsius–Kelvin conversion:

Results of kinetic theory of gases:

(monatomic gas)

(diatomic gas)