SC300 Big Ideas in ScienceUnit 3: Electromagnetic Waves

Bronwyn Scott

BScott@kaplan.edu

AIM: BScottKaplan@aol.com

Welcome to Seminar Three

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Doing research on Greyland Beach near Westport, Washington(2004)

Agenda

1. Discussion Boards

2. Electromagnetic (EM) Spectrum:

a. microwaves

b. infrared waves

c. visible light waves

3. Unit 4 Discussion Groups

4. Q & A

Discussion Boards (35 points)

1. References transform random opinions into supported points of view.

2. ≥2 substantial replies that further the discussion

No: “I really liked your post…”

“I agree…”

Yes: “I really liked your post and I did some further research and found this additional information…”

“I agree and was able to find this website, but how does that compare …”

Electromagnetic (EM) Spectrum

Image credit: http://www.barnabu.co.uk/cosmic-microwave-background-radiation-in-google-earth/

Cosmic microwave background radiation

These are discussed in Chapter 15 on page 317

Man-made microwaves

Image credit: Microsoft Clip Art

What do you think…

1. Your Grandma Pauline has just won a microwave oven in a radio contest.

- When it arrives at her house, it sits on her counter for a month, unused

- One afternoon, she tells you that she is afraid to use it because ,"If I stand too close, I'll get radiated!”

Explain to your Grandma the difference between the waves that are used in a microwave oven and the dangerous nuclear radiation she fears.

Infrared Waves

Searchwarp.com. (2007, Oct.). Retrieved October 29, 2010, from the World Wide Web: http://searchwarp.com/swa262670.htm

Infrared Waves

Image credit: NASA/JPL-Caltech/IPAC

The primary source of infrared radiation is heat or thermal radiation.

Some animals can “see” in infrared!

Image credit: Sichert, Andreas B., Friedel, Paul and van Hemmen, J. Leo. Snake’s Perspective on Heat: Reconstruction of Input Using an Imperfect Detection System. Physical Review Letters. 97 (2006).

What do you think…

2. Use these spooky infrared pictures of a cat to give some proof to Grandma Pauline that a cat's nose is always cold.

Image credit: SE-IR Corporation, Goleta, CA

What do you think…

• If you took a similar infrared photo of your body, what parts would you expect to show up as brightest orange? What parts would be blue? Explain.

What do you think…

• If you took a similar infrared photo of your body, what parts would you expect to show up as brightest orange? What parts would be blue? Explain.

Image credit: NASA/JPL-Caltech/IPAC

Cold Noses vs. Cold Lips…

Image credit: NASA/JPL-Caltech/IPAC

What do you think…

• After Grandma Pauline starts thinking about electromagnetic waves, she asks you to explain:

- If radio waves and microwaves are both electromagnetic waves, why she can’t listen to KROQ-FM on her new microwave oven?

Visible Light Waves

Visible Light Waves

Image credit: http://scienceblogs.com/startswithabang/2009/12/the_good_and_bad_of_the_new_hu.php

Photosynthesis

Grow ‘Em Plant Propagation. (n.d.). Retrieved October 28, 2010. World Wide Web: http://grow.ars-informatica.ca/gallery.php?img=61

Unit 4 Discussion GroupsBioenergy Geothermal Nuclear

Coal Hydrogen Oil

Solar Hydropower Wind

Fusion Natural Gas

• Suggestion:Thu & Fri: collaborate, strategize, & divide up the workFri – Sun: make separate posts, being careful never to repeatSun & Mon: comment on the suitability of other groups' energy sources

Mon & Tue: vote and explain your vote

Questions?

Image credit: Microsoft Clip Art