Createa PowerPoint presentation that contains the various heat transfer mechanisms, some applications of ideal gas law, and the kinetic theory.In your presentation, be sure to include the following:
- Include a title and references slides.
- Research and provide content for the following topics.
Compare and contrast the three heat transfer methods (conduction, convection, and radiation) with examples.
Describe the relationship between temperature, pressure, and volume in the ideal gas law with examples.
Explain the concept of the kinetic theory of gases. - Include a minimum of 10 slides, not counting the title and references slides.
- Adhere to general best practice to use no more than 5–6 bullet points per slide.
- Use presenter notes to provide the details of your presentation.
- Insert appropriate images, diagrams, and tables to enhance your content.
- Use at least two scholarly references in your presentation. Include APA Style citations and references for each source used.
- Use the CSU Online Library for assistance with the research.
- Utilize the Writing Center for assistance with proper formatting and APA Style, or view this tutorial for additional information PowerPoint Basics tutorial .
PHY 1301, Physics I 1
Upon completion of this unit, students should be able to:
7. Describe fundamental thermodynamic concepts.
7.1 Explain the various heat transfer mechanisms with practical examples.
7.2 Recognize the ideal gas law and apply it to daily life.
7.3 Describe the relationship between kinetic energy and the Kelvin temperature.
Course/Unit
Learning Outcomes
Learning Activity
7.1
Chapter 13
Chapter 14
Unit VII PowerPoint Presentation
7.2
Unit Lesson
Chapter 13
Chapter 14
Unit VII PowerPoint Presentation
7.3
Unit Lesson
Chapter 13
Chapter 14
Unit VII PowerPoint Presentation
Chapter 13: The Transfer of Heat, pp. 360–379
Chapter 14: The Ideal Gas Law and Kinetic Theory, pp. 380–400
Unit Lesson
UNIT VII STUDY GUIDE
Heat Mechanism and Kinetic Theory
PHY 1301, Physics I 2
UNIT x STUDY GUIDE
Title
The Three Methods to Transfer Heat
The above image illustrates the three heat transfer methods. The sun heats the Earth by radiation, the
surface of the Earth heats the air by conduction, and the warm air rises by convection.
What is heat? Heat is energy that moves from a high-temperature object to a low-temperature object. Its unit
is the Joule (J), but sometimes it is measured with the kilocalorie (kcal). The conversion factor between the
two units is 1 kcal = 4186 J. The transfer of heat is processed by the following mechanisms.
Conduction is the process in which heat is transferred through a material. The atoms or molecules in a hotter
part of the material have greater energy than those in a colder part of the material, and thus the energy is
transferred from the hotter place to the colder place. Notice that the bulk motion of the material has nothing to
do with this process. You can easily find examples of conduction. A radiator in your house is one of them. If
you put an object on the radiator, the object will become warmer. Another example is when you pour the
brewed hot coffee into a cold cup; the heat from the hot coffee makes the cup itself hot.
The heat Q conducted during a time t through a bar of length L and cross-sectional area A is expressed as
Q = kA (dT) t / L. Here, k is thermal conductivity, and it depends on the substance; dT is the temperature
difference between the higher temperature and the lower temperature of the bar.
Convection is the process in which heat is transferred by the bulk motion of a fluid. According to the ideal gas
law for constant pressure, the volume (V) is proportional to the temperature (T). V increases as T increases,
and the density decreases within the constant mass. Warm air rises and cooler air goes down; this circulation
makes the energy transported. The generated energy from the center of the sun is transported by convection
near the photosphere. Cool gas sinks while bubbles of hot gas rise. There is a patchwork pattern of small
(average diameter about 700 km), transient (average lifetime from 5 to 10 minutes) granules. The granulation
is the visible consequence of the convection.
Radiation is the process in which heat is transferred by light, electromagnetic waves. An electromagnetic
wave consists of an oscillating magnetic and electric field moving at the speed of light, c = 300,000 km/s. This
method does not need a material medium, unlike the two other methods. Every object absorbs and emits
electromagnetic waves at the same time. When an object absorbs and emits radiation perfectly, it is called a
blackbody. The emitted light by a blackbody is called blackbody radiation, and its spectrum is a continuum
because interactions between severely packed atoms are so strong that all detailed spectral features do not
remain. Also, they are in thermal equilibrium, so blackbody radiation only depends on its absolute
temperature, not on the chemical composition of the object.
After John Maxwell’s theory of electromagnetism appeared in 1864, many attempts were made to understand
blackbody radiation theoretically. None succeeded until in 1900 Max Planck postulated that electromagnetic
energy can propagate only in discrete quanta, or photons, each with an energy of E = h. This brilliant
German physicist then derived the spectral intensity relationship, or Planck radiation law, a log-log plot
between intensity and temperature. These masterpieces are a combination of classical works by Wien’s law
PHY 1301, Physics I 3
UNIT x STUDY GUIDE
Title
and Rayleigh-Jeans’ law (Nave, n.d.). Wien expressed the wavelength max at which the maximum intensity of
blackbody radiation is emitted by Wien’s displacement law: max = 2.898 10-3 / T [m]. Here, T is the surface
temperature. For example, the continuum spectrum from our sun is approximately a blackbody, peaking at
max 500 nm; therefore, the surface temperature must be near 5800 K. The emitted maximum flux of a star
determines the color with the maximum intensity of blackbody radiation formula. Meanwhile, Rayleigh-Jeans’
distribution works at high temperatures and long wavelengths, which have low frequencies (Nave, n.d.). It is
useful to obtain the brightness temperature in radio astronomy. For further explanation, please visit the
webpage “Blackbody Intensity”.
The Sun’s Influence on the Earth
The sun’s violent activities such as erupting solar flares, coronal mass ejections, and solar winds are greatly
influencing the Earth as well as the rest of the solar system. The sun is one of 200 billion stars that exist in the
Milky Way galaxy. The size and mass of the sun are enormous. The size is about 1,390,000 km and the mass
is 1.989 × 1030 kg. The sun possesses approximately 99.8% mass of the solar system. The surface of the sun
is called the photosphere, a visible atmosphere with a depth of about 500 km, and its blackbody temperature
is about 5800 K.
There are violent regions that can affect the Earth’s environment, such as sunspots (11-year cycle), flares,
and the corona. The sunspots look darker because the temperature is relatively lower, about 3800 K. They
appear dark only against the bright sun and would still be brighter than the full moon when placed in the night
sky! These spots are produced by magnetic field interactions, and the diameter of one is about 50,000 km.
The magnetic field in the sunspots is about 1,000 times stronger than average. Hot gas ejected from the sun
often follows the magnetic field line and traces out the loop structure of the magnetic field, called
prominences. Sometimes we observe a brief eruption of hot, ionized gases from a sunspot group. This
phenomenon is known as a solar flare. These magnetic storms are closely related to sunspot cycles. In 1 or 2
years after the maximum sunspots, non-repetitive magnetic storms follow, and then a strong aurora can be
observed. Meanwhile, just after the minimum of sunspots, repetitive magnetic storms come, and then a weak
aurora appears.
The above layer of the photosphere is called a chromosphere and has less dense gas with high temperature.
We can detect visible UV and x-ray lines from highly ionized gases. Temperature increases gradually from
about 4,500 K to 10,000 K, and then jumps to one million K. One distinctive feature is a spicule, which
extends upward from the photosphere into the chromosphere along the boundaries of super granules.
Spicules are filaments of cooler gas from the photosphere that rise up into the chromosphere. Each of them
can last about 5 to 15 minutes. The above of chromosphere is called a corona. The corona extends up to a
few million kilometers, and the temperature is about several million K with an extremely low density. Coronal
gas is heated through motions of magnetic fields anchored in the photosphere below. X-ray images of the sun
reveal coronal holes. These arise at the footpoints of the open field lines and are the origin of the solar wind.
A coronal mass ejection is a much larger eruption that involves immense amounts of gas from the corona. We
can see the corona during a solar eclipse. The sun has a strong magnetic field, and the magnetosphere or
heliosphere extends out beyond the orbit of Pluto.
The solar wind, the outflow of low-density charged particles (mostly electrons and protons), moves with a
speed of 450 km/sec. An extreme magnetic phenomenon like an aurora on the Earth happens because of
high energy particles from the solar wind and the flares. According to the solar wind research space probes
such as Wind, ACE, and SOHO, there is a dynamically stable position, about 1.6 × 106 km from the Earth.
Moreover, the solar wind affects the tail parts of comets and the orbits of space probes. The output of solar
energy is not always constant. There was a minimum period of sunspot activity in the late 17th century, called
the Maunder Minimum. This period was strangely consistent with the cold period, or the Little Ice Age in
northern Europe. It is estimated that solar energy has been increased by about 40% since the formation of the
sun. The age of the sun is about 4.5 billion years old. About half of the hydrogen has been consumed since
the birth of the sun, so there are about 5 billion years left until the sun dies.
The solar wind can have a large influence on our planet, particularly in times of the active sun (near sunspot
maximum) when the wind is strong and can contain bursts corresponding to flares and coronal mass ejections
from the sun. The solar wind has a significant influence on our ionosphere, the Earth’s magnetic field, on
Earth’s auroras, and on telecommunication systems. For example, there are reasons to believe that a burst of
http://hyperphysics.phy-astr.gsu.edu/hbase/mod6.html#c5
http://csep10.phys.utk.edu/astr161/lect/earth/atmosphere.html
http://csep10.phys.utk.edu/astr161/lect/earth/magnetic.html
http://csep10.phys.utk.edu/astr161/lect/earth/aurora.html
PHY 1301, Physics I 4
UNIT x STUDY GUIDE
Title
particles from a coronal mass ejection detected 5 days earlier by SOHO may have killed the Telstar 401
communication satellite on January 11, 1997.
Ideal Gas Law
When a gas has a very low density (where the average distance between molecules of the gas are very
large), it is called an ideal gas. The ideal gas law is the relationship between pressure, volume, and
temperature. More exactly, the absolute pressure (P) of an ideal gas is proportional to the temperature and is
inversely proportional to the volume (V).
Here, R is the universal gas constant, and n is the number of moles. One gram-mole of a substance contains
as many particles (atoms or molecules) as there are atoms in 12 grams of the isotope carbon-12. According
to experiments, 12 grams of C-12 have 6.022 x 1023 atoms. The number of atoms per mole is called
Avogadro’s number NA. The ratio between the universal gas constant R and the number of moles n is defined
as Boltzman’s constant k. Please note, the product n and NA is the total number of particles. So, the product
of pressure P and volume V is expressed as NkT.
If the temperature is not changing, that is, T = constant, the pressure P is inversely proportional to the volume
V of the gas: PV = constant. This is called Boyle’s law. See Figure 14.6 on p. 385 in the textbook. The
respiration through the lungs/alveoli allows the oxygen into and the carbon dioxide out from our bodies. When
the lung volume increases by the contraction of the diaphragm and other respiratory muscles, the pressure of
the lung decreases by Boyle’s Law (PV = constant), and this leads the inward air movement to the lung.
If the pressure P is constant, the volume V is proportional to the temperature T: V / T = constant. This is
called Charles’ law.
Kinetic Theory of Gases
The kinetic theory of gases illustrates the microscopic behavior of elementary particles, and it describes the
macroscopic picture of the motion. We assume that the number of particles is very large. Also, the separation
between particles is large. The motion of particles is assumed to be random with a constant speed. The
kinetic theory states that the kinetic energy of the gas particles is proportional to the Kelvin temperature of the
system. The Kelvin temperature is also proportional to the product of the mass of the particles and the square
of the rms speed of the particles. The internal energy of the gas is also related to its Kelvin temperature.
In this unit, we have explored the detailed mechanism of heat transfer methods with the behavior of the ideal
gas. In addition, the kinetic theory and ideal gas law explain the various physical phenomena. In the next unit,
we will utilize these concepts to understand thermodynamics laws.
Reference
Nave, R. (n.d.). Blackbody intensity as a function of frequency. HyperPhysics. http://hyperphysics.phy-
astr.gsu.edu/hbase/mod6.html#c5
Nongraded Learning Activities are provided to aid students in their course of study. You do not have to submit
them. If you have questions, contact your instructor for further guidance and information.
1. Solve questions 46 and 47 on p. 379 in the textbook.
2. Solve questions 66 and 67 on p. 400 in the textbook.
PV = nRT = NkT
- Course Learning Outcomes for Unit VII
Required Unit Resources
Unit Lesson
The Three Methods to Transfer Heat
The Sun’s Influence on the Earth
Ideal Gas Law
Kinetic Theory of Gases
Reference
Learning Activities (Nongraded)