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Simple Thermodynamics of Transportation
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Overview
Grade Level: 9-12
Background Information:

The American way of life has advanced to include a strong transportation infrastructure throughout the country. Business travelers get up in the morning on the east coast, fly to the west coast for a meeting, and fly home again. Families make dozens of trips a day from their homes going to school and work, to the store, to friends, relatives, and activities. All of these trips require energy. To date, the majority of our transportation needs have been met by using limited resources such as fossil fuels and lumber. These resources are running low, and people have been trying to invent new, more energy efficient modes of transportation. To do this requires an understanding of energy transformations that occur to make an engine work and a vehicle go. It also requires an understanding of the laws of thermodynamics.

In this lesson, students will watch videos about various modes of transportation, they will examine the energy transformations that occur in each, and they will be introduced to the laws of thermodynamics. These lessons can be adapted to fit the needs of your class by adding more or taking away information about the laws of thermodynamics.

 

Curriculum Connection

Integrate lessons with a social studies class learning about how the history of transportation shaped American life. Search the AFG video database for more videos on transportation history. Students in English classes might read 18th century American literature to get a feel for the pace of life then, or they might write a fictional journal outlining the differences in life once 'the train came to town.' In Math classes, students might calculate the time necessary to complete a cross-country trip using different modes of transportation.

Content Standards
Related National Standards:

This lesson addresses the following National Content Standards found at: http://books.nap.edu/html/nses

 

Content Standard B: As a result of their activities in grades 9-12, all students should develop understanding of:

  • Conservation of Energy and Increase in Disorder
    • The total energy of the universe is constant. Energy can be transferred by collisions in chemical and nuclear reactions, by light waves and other radiations, and in many other ways. However, it can never be destroyed. As these transfers occur, the matter involved becomes steadily less ordered.
    • All energy can be considered to be either kinetic energy, which is the energy of motion, potential energy, which depends on relative position, or energy contained by a field such as electromagnetic waves.
    • Heat consists of random motion and the vibration of atoms, molecules, and ions. The higher the temperature, the greater the atomic or molecular motion.
    • Everything tends to become less organized and less orderly over time. Thus, in all energy transfers, the overall effect is that the energy is spread out uniformly. Examples are the transfer of energy from hotter to cooler objects by conduction, radiation, or convection and the warming of our surroundings as we burn fuels.
Extension Web Sites from PBS:

The American Experience - New York Underground
Learn how advancements in transportation technology have changed people's lives.

The West - The Transcontinental Railroad
This is the railroad that changed our country. Examine America before and America after the Railroad came through.

Newtons Apple - Locks and Dams
Why are dams sometimes necessary? How do locks and dams work? What are some of the effects of a lock and dam system on the river's environment?

Newton's Apple - Car Engines
Model the energy transformations involved in making cars go!

Newton's Apple - Riverboats
Learn how steam can be converted to make riverboats go!

Activity 1: Energy to Go!
Time Allotted:

40 minutes

 

Materials:

No special materials are necessary

 

Objectives:
  • Students will trace energy transformations that occur in different types of transportation.
  • Students will understand that most of our energy comes from the sun.
  • Students will learn the basics of the laws of thermodynamics.


Watch the AFG Video Segment:

Misty Fjords Kayak Rangers
Sea kayaks are the mode of transportation of choice for the rangers that patrol the Misty Fjords Wilderness Area in Alaska.

 

Teaching Strategies:
  1. Explain that traveling takes Energy. Then, have students brainstorm words associated with energy.
  2. Discuss the scientific meaning of energy (energy = the ability to do work; Work = the movement of matter)
  3. Introduce the fundamentals of the laws of thermodynamics.
  4. According to the first law of thermodynamics, Energy is neither created nor destroyed. Energy can be converted from one type to another, though, according to the second law of thermodynamics; No energy transformation is 100% efficient. Thus, each time you exchange energy, some of it is lost as useless heat energy called entropy.
  5. Introduce various forms of energy including: light (electromagnetic), gravitational, mechanical, chemical, nuclear, sound, electrical, and thermal. Make a list of these energy types on the chalkboard or overhead.
  6. Ask students to consider where the energy came from for the Kayakers to move the boat. Have them make a diagram illustrating as many energy transfers as they can think of involved in moving a Kayak. Encourage them to trace the energy back to it's ultimate source, the sun. A possible answer is that the mechanical energy to move the boat came from the chemical energy in the Kayakers food, which was produced by photosynthesis using light energy from the sun.
Activity 2: Lock, Stock, and Barge
Time Allotted:

30 minutes

 

Materials:

No special materials are needed

 

Objectives:
  • Students will learn the principles behind the use of locks in river navigation
  • Students will illustrate energy transfers that occur as rivers are used for transportation
  • Students will understand the benefits of barges used in shipping from an energy perspective.
  • Students will show that the ultimate source of energy used in river transit is the sun.
  • Students will apply the laws of thermodynamics to barge shipping.
Teaching Strategies
  1. Students will be asked to make a diagram showing the energy transformations used in getting ships up and down rivers. Through this, they will understand how the sun's energy has been converted, through multiple energy transformations, to do useful work for humans.
  2. Students should have a concept of energy transformations, or they should be introduced to it here. See activity 1 for an introduction to energy. These same steps can be applied here.

  3. Watch the AFG Video Segment
    Play This Clip
    McAlpine Locks and Dam on the Ohio River
    In order to provide a navigation system for the Ohio River, the McAlpine Locks and Dam system was built at Louisville, Kentucky.
    Note: Observe how barge traffic works and how they use locks to get up and down the river. Clip starts at "the McAlpine Lock and Dam project is located at Louisville Kentucky." Watch to the end.


  4. Ask students to draw a sketch of a lock at a dam and show how it works.
  5. Discuss their answers. Ask them to explain the lock in terms of energy transformations.
  6. They should then draw an entire river from an inland port to a coast. Their goal is to illustrate all the energy transformations that take place in moving barge traffic. Ask them to consider the ultimate source of energy for moving barge traffic on rivers. Creativity, as long as it is correct, is to be encouraged.
Assessment:
This is an example of an answer students might produce:
  1. Nuclear energy in the sun is converted to electromagnetic energy at the surface of the sun.
  2. Electromagnetic energy travels to earth and then is converted to thermal energy as it heats up molecules at the oceans surface causing evaporation.
  3. Thermal energy produces winds on earth, moving water over land.
  4. Thermal energy leads to condensation in clouds, which are affected by gravitational energy and fall to earth.
  5. Gravitational Energy continues to pull the water downwards, leading it into rivers and back towards the ocean.
  6. Barges can take advantage of this gravitational energy, floating on the river down towards the ocean.
  7. Meanwhile, the barges are burning chemical energy in the form of fossil fuels that was originally derived from the sun during photosynthesis by ancient organisms.
  8. This chemical energy is converted into heat and mechanical energy by the engine of the barge to move it upriver and to keep it on course.
Activity 3: Hero's Steam Engine
Time Allotted:

One hour

 

Materials:
  • Student Instructions
  • Bunsen burners
  • Matches
  • Stop watch
  • Per group:
    • Strait pin
    • Soda can
    • 1 cm square of aluminum (cut from soda cans)
    • 1 small cork
    • Styrofoam cups to fit over the top of the soda can
    • Good, wide sticky tape. Duct tape works well. (Be sure to test your brand of tape as some won't work and will thus make the activity impossible)
    • Goggles for each person

 

Objectives:
  • Students will use the concept of energy transformations to build a simple steam engine.
  • Students will trace the transformation of energy through the steam engine system.
  • Students will develop an understanding of energy transformations in the steam engine system so that they can apply their knowledge towards making an improved model.
  • Students will apply the laws of thermodynamics to the principles behind a steam engine.
Teaching Strategies:

In this activity, students will build their own steam engine and they will apply the principals behind steam power to the transformation of energy and the laws of thermodynamics. It is more fun to make this activity into a contest in which case the teacher will control the Bunsen burner, but it is also possible to have groups work entirely on their own, in which case each group will need their own Bunsen burner.

Watch the AFG Video Segment:

Skagway Steam Train
Originally built to link Skagway to the location of the Klondike Gold Rush, the White Pass Railroad has transformed itself into a scenic attraction.
 
  1. Point out how steam engines changed life for people and how they were made possible by a good understanding of physics.
  2. Students should be familiar with the Laws of Thermodynamics and with the general principle of energy transformations. Otherwise, you should introduce them now (see Activity 1).
  3. Break students into groups of two and distribute student handouts.
  4. You may want to demonstrate the steam engine so that students can see how it functions (see student handout below for directions on how to make the engine. Similar steam engines are available from scientific supply catalogues such as Wards and are usually called 'Hero's Steam Engine'.
  5. Have students follow the instructions on the student handout to build their steam engine. Encourage them to think about making it more efficient and faster by having a contest. Tell them that the group with the longest spin-time, and the group with the most vigorous spinning will win a bonus (extra credit, chocolate or whatever works in your classroom).
  6. As students complete their engines, have them come to you at a Bunsen burner. They should wear goggles and one student should hold the engine by the cork over the Bunsen burner. If built correctly, it should start to spin after the water heats up. Start your stopwatch and stop when it finishes spinning. Well-built engines have spun for over two minutes in our classroom, though getting one to spin for 10 seconds is respectable.
  7. If materials and time allow, students may return to their lab stations to try to improve on their design.
  8. Have students clean up and restock stations. Then they should finish their analysis questions on the student handout.
Related Web Sites:

See the Newton's Apple - Riverboats activity for more background information.

Assessment:

Rules of the Spin - How you grade a students finished product is up to you. It is sometimes hard to get engines to spin, so I usually don't use spinning as a criteria except as an opportunity for extra credit as described above. Students will also use a variety of techniques to try to get it to spin longer and faster, such as holding it higher and lower in the flame, or removing it from the flame altogether. Others will adjust their design to include more water, more or less tape, more or fewer holes, etc. I like to encourage creativity in this regard as it shows me that they understand what is happening inside the engine, but some other people like to develop stricter rules. Have the student build at least one according to the directions before starting to experiment with materials. I suggest that you build a few yourself before assigning this engine so that you understand the pitfalls and the possibilities!

 

Answers to Analysis Questions
  1. Answers will vary
  2. Answers will vary. Design, construction, weight, efficiency will all cause differences.
  3. Less tape and better seals are two of the main factors that allow engines to work better as they reduce the amount of friction and keep fuel from escaping. Holding the can at the right point in the flame will keep the fuel burning steadily and will not cause it to overheat. More water means more fuel, but it also makes the can heavier, so some students may find a good balance.
  4. Pictures should indicate the heating of water inside the can excites the molecules, turning them into steam, and when the pressure builds up inside the can the steam escapes, driving the can.
  5. Answers will vary.
  6. Chemical Energy in the gas was converted to heat energy in the flame, which broke down the chemical energy in the water to create mechanical energy in the spinning of the energy. Heat was also lost during this experiment.
  7. Energy is neither created nor destroyed; the can did not spin of its own volition, but energy from the gas was converted into mechanical energy. No energy transformation is 100% efficient. During each step, energy that had been stored in the chemical bonds in the gas was lost to the environment as heat energy or entropy.