29 November Science 7 Energy and Hot Air Balloons (leading to summative project)

Captains–to choose groups

Questions about energy?

A pendulum to illustrate energy transformation–Gravitational potential energy transformed to Kinetic energy and back. What is the relationship between work and energy? How does the Conservation of Energy apply.

What is heat? What is temperature?

Three energy problems (complete these in your digital science notebook and be ready to share/submit in the next two weeks):

  1. Climbing the stairs. Calculate the work you do to climb the outside stairs from the ground level (HOP) to the third floor. Calculate the food you need to eat (kind and amount) to give you the energy to climb the stairs. Show your work.
  2. Energy toy 1. See video. Explain using concepts and quantities from our study of motion and energy.
  3. Energy toy 2. See video. Explain using concepts and quantities from our study of motion and energy.

View the wonderful video episode about energy CHANGE from The Ring of Truth. Follow closely the example of the cyclists in the Tour de France. How does the author use the unit of a “jelly donut” to examine ideas of energy–like the Conservation of Energy? Notice that the video explores and important cross-cutting concept in science: Stability and Change.  https://www.youtube.com/watch?v=Nk8CQNThbc0

Begin construction of  tissue paper hot-air balloon. During this process, if you have any time when you are waiting, catch up on your digital science notebook, your blog, and reading.

Video clip from famous series: The Search for Solutions


Look at these explanations from 2012 Sci 7. What do you think?


Some web links. http://rfrazier.msblogs.aes.ac.in/science-7/web-links/web-links-for-energy-science-7/

You might find these data and ideas interesting / useful.


 Be sure to document (photos, sketches, written description) the process of making the tissue-paper hot air balloons in your digital science notebook. (Take measurements.) Look at 7th graders’ ideas about the hot air balloon linked in the class blog post for 29 November.History of Hot Air Balloons http://www.ballooning.es/uk/hot-air-balloon/history.php

How could you find the density of air (by measurement)?

What is the relationship of the density of air to air pressure?

How might the temperature of air affect its density?

What happens to the motion of the molecules of the different gases that make up the atmosphere when the temperature changes? What does this have to do with energy? Try this simulation: https://phet.colorado.edu/en/simulation/gas-properties


From Wikipedia entry for Composition of the atmosphere:

Major constituents of dry air, by volume[6]
Gas Volume(A)
Name Formula in ppmv(B) in %
Nitrogen N2 780,840 78.084
Oxygen O2 209,460 20.946
Argon Ar 9,340 0.9340
Carbon dioxide CO2 400 0.04[7]
Neon Ne 18.18 0.001818
Helium He 5.24 0.000524
Methane CH4 1.79 0.000179
Not included in above dry atmosphere:
Water vapor(C) H2O 10–50,000(D) 0.001%–5%(D)
(A) volume fraction is equal to mole fraction for ideal gas only,
also see volume (thermodynamics)
(B) ppmv: parts per million by volume
(C) Water vapor is about 0.25% by mass over full atmosphere
(D) Water vapor strongly varies locally[4]

About rfrazier

AES profile = http://aes.ac.in/viewprofile.php?u=6946
This entry was posted in Science 7. Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *