Science of Transistor Radios

Today's column listed an article on the transistor radio:
Transistor radio story posted October 18, 2008

The story offers a good way to interest some people in science and engineering. For example, a comparison and contrast could be done on the effect of transistor radios and MP3's on teen culture, someone might want to build a transistor radio or a computer, one might study electricity, someone else might study sound waves. A news story on historical development of the transistor radio could, thus, lead to a class full of students working on science activities, all different, yet, linked by the transistor radio. Because the students could select something of interest to them, it is likely they would be engaged in their studies.

More Sources:

1. http://www.vintageprojects.com/radio/transistor-radio.pdf
2. http://www.pcmech.com/byopc/
3. http://en.wikipedia.org/wiki/Heathkit
4. http://www.retrothing.com/2006/03/heathkit_h8_dig.html
5. http://blog.modernmechanix.com/2006/06/23/the-new-heathkit-personal-computing-systems/
6. http://www.heathkit-museum.com/hvmhstory.shtml
7. http://www.heathkit-museum.com/computers/hvmec-1.shtml
   
8. [Please add more in comment sections, if you know of good links. Thanks.]
   

Have fun,

Dr. J

Ever since Ozmonty ...Australian things are popping up. Here are some genetics ideas...

Wild virus attacks rabbits, your teacher says...Myxomatosis...Hmmm! It's a mystery because the virus no longer kills the rabbits. Why do they want to kill the rabbits. It must come down to money. What did the poor rabbit do to them? Ruined the human food supply? What? Are you kidding? How can we find out about it. Well, let's search the net and see what we come up with. Here are some leads.

First, you should do some research. Skim through these and find some points you can use. Be sure to site them with website and date accessed, according to the style manual your school or teacher uses (probably MLA, but, perhaps in science, CBE)
http://www.csiro.au/science/MyxomatosisHistory.html

Here's the wiki site. It is helpful, but, a lot of schools are snobby about it, So, don't use only wiki. Still, it is a good starting point and can bridge you up to journal articles:
http://en.wikipedia.org/wiki/Myxomatosis

Here's a site that is biased in favor of humane treatment of rabbits:
http://www.ozrabbits.com/myxomatosis.html

Here's an abstract from a journal article. If you go to one of the colleges, the librarian can help you get a copy of the whole article. This is the level of reading that you should start to be introduced to on the high school level (so you are not shocked when you get to college and they expect you to find and read them on your own without being told...). Try to find more articles on this level:
http://www.publish.csiro.au/paper/ZO9900697.htm

Great, we've got some basic material. What do we need next? A plan. That's it, we need a plan. Just like a video game strategy, we need a Rabbit Population Mystery Strategy.

Time for the H.O.T. Skills Wheel(TM).
Knowledge
So Knowledge...Hmm, we can read and take notes on the articles we found. We can also find more articles. We could cut out some newspaper articles or find some pictures, perhaps.
Understanding
Can you paraphrase what the articles said? That means, can you say them in your own words.
Application
How can you use this information? Can you suggest public policies from it?
Analysis
Can you critique the journal articles you found? Can you reanalyse some of the data you read about? Can you analyze data you collected? Do you know whether to use statistics or not? What statistics to use if you do need to use it?
Synthesis or evaluation
(The highest two thinking levels are sometimes switched)

Synthesis
What can you create? Build? Design? Can you design an experiment to test a new hypothesis you have made based on your analysis of the information you gathered from material you read?
Evaluation
Can you evaluate the results of your experiment and library research? Can you suggest public policy? Should a rabbit law be made? What should it say? Why?

Convection, Conduction, and, Radiation

Today, a student asked me a question about conduction, convection and radiation: "I am always confused between the difference of conduction, convection and radiation. What is being used in pouring hot water from a thermos?"

Students will often ask things that are assigned as homework. This might have been a homework question, or, it might have been genuine curiosity. I am always glad when students are curious.

I've taken the liberty of discussing the topic here because it is a topic on many state standards.

For these types of questions, try to guide a student in finding an answer. In this way, he or she is likely to remember the content learned. Here is a sample set of guiding questions and activities. I have also included some movies. Your students might be able to make movies that are more exciting and helpful to them. Review the "Botany Beat" or Tomato movies for some ideas. Here is one student's movie:




First, have you defined all the words? (You can use the dictionary links at the bottom of the page. Be sure to note down the date and the source you used.)

Conduction is ________________________________________________________
Here is a simulation on conduction:


And, here is an animation about conduction:



Convection is ________________________________________________________

Here is a movie on convection currents:


What do hot and cold have to do with convection?


Here's another convection movie showing some experiments and relating them to every day life.





Radiation is ________________________________________________________

Here is an animation on radiation and convection:


If you have trouble remembering them, try writing the definitions three or four times , or, try drawing a picture or writing a song about each one.

Also, try discussing these ideas with your friends or where you get snacks after school or with a mentor or adult in your family or community. These things can help you to remember them.



Did you brainstorm about them?



Do you have a thermos? If you don't have one, try to borrow one, otherwise, the question will be hard to answer.



If you put hot water in a thermos, can you feel the heat outside the thermos when you hold it?



What about if you put your hand over the thermos, can you feel heat, even when you are not touching anything?



What if you compare putting a plastic spoon into the hot water with putting a silver spoon into the hot water. What happens?



Think of things you know, for example:

The sun rays radiate.

The convection oven has heat rise and fall in circles.

A copper wire conducts electricity.

Now, think again about the question. When you pour hot water from a thermos, do you feel heat without touching it?



Does some heat stay in some matter, yet move?



Does some heat transfer from the hot water to the bowl or sink you are pouring it into?



Now that you have thought about all these things, and tried some of them, I think you can be confident of the answer that you develop. Be sure to back up the answer with why you picked it. You might speak, write and draw your answer, too. Let me know what you find out. Write back if you are still stuck. Dr. J

Related links:
http://home.howstuffworks.com/thermos1.htm

http://www.newton.dep.anl.gov/askasci/phy99/phy99x81.htm

http://www.sciencebuddies.org/mentoring/project_ideas/Phys_p032.shtml

http://www.comsol.com/showroom/gallery/1448.php

Update... 2009
rockytop.adams12.org/growlercore/documents/Weather_notes.ppt
http://www.accidentalscientist.com/2009/08/conduction-convection-and-radiation-and.html
(c)2007, 2008, 2009 J. S. Shipman