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Scaling the electromagnetic spectrum. Boxing out waves. The First Big Idea. Scale describes matter and predicts behavior . . The “Other” Big Ideas of Nano. Structure of Matter Forces and Interactions Quantum Effects Size-Dependent Properties. Other Big Ideas - continued. Self-assembly

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Scaling the electromagnetic spectrum

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Scaling the electromagnetic spectrum

Scaling the electromagnetic spectrum

Boxing out waves

The first big idea

The First Big Idea

  • Scale describes matter and predicts behavior.

The other big ideas of nano

The “Other” Big Ideas of Nano

  • Structure of Matter

  • Forces and Interactions

  • Quantum Effects

  • Size-Dependent Properties

Other big ideas continued

Other Big Ideas - continued

  • Self-assembly

  • Tools and Instrumentation

  • Models and Simulations

  • Science, Technology, and Society

An amazing scale

An Amazing Scale

  • More than you can see

Wavelength is the key

Wavelength is the Key

What we see is much less than what we get.

Opensource Handbook of Nanoscience and Nanotechnology. Illustration by KristianMolhave

Nanoscale 1 100nm

Nanoscale =1- 100nm

10-7 = 0.0000001 = 100 nm

Visible Light 390-750nm

Scaling the electromagnetic spectrum

10-9 = 0.000000001 = 1 nm

X-ray .01 to 10nm



  • Transfer energy without transferring matter

Electromagnetic energy

Electromagnetic Energy

Determined by wavelength and frequency.

  • E = mc2

  • c = 2.9979 x 108 m/s

Dual nature of light

Dual Nature of Light

  • Light is also photons (particles)

    • Zero mass and zero rest energy

    • Can be destroyed and created

    • Can have particle-like interactions with matter

Electricity and magnetism

Electricity and Magnetism

  • Magnetism and electricity move together in the EM spectrum.

Diagram from Schneider, Remote Sensing and the Global Environment,

Appearances may deceive

Appearances May Deceive

  • Optical properties vary at the nanoscale.

Image source: L. R. Hirsch, R. J.Stafford, J. A. Bankson, S. R. Sershen, B. Rivera, R. E. Price, J. D. Hazle, N. J. Halas, & J. L. West, Proc. Natl. Acad. Sci. USA, 100, 13549-13554 (2003).

Blocking out signals

Blocking Out Signals

  • Faraday Cage

Faraday cage

Faraday Cage

  • How does it work?

Blocking signals activities

Blocking Signals Activities

  • Materials Needed

    • Cell phone or small radio

    • Small box with lid

    • Aluminum foil

    • Aluminum screen

    • Scissors

    • Tape and/or stapler

    • ruler

Activity control experiment

Activity – Control Experiment

1. Turn on radio and set in box.

2. Place lid on box.

3. Turn off radio.

4. One (or more) group test with cell phone if available.

Activity box the signal

Activity – Box the Signal

  • Wrap box and lid separately in aluminum foil (ensure snug fit).

  • Set radio in box.

  • Open box slightly (experiment with opening size).

  • One (or more) group test with cell phone if available.

Activity screen the signal

Activity – Screen the Signal

  • Make a cylinder with aluminum screen.

  • Leave one end open.

  • Make a prediction.

  • Place radio inside.

  • Close other end of cage.

  • Test with a cell phone if available.

Wavelength and frequency activity

Wavelength and Frequency Activity

  • Wavelength

    • l = c/f

      • C = 3.0 x 108 m/s

  • Example

    l = (300,000,000m/s) / (540,000 Hz) = 55.6 m

  • Frequencies

    • AM radio: 540-1640 KHz

    • FM radio: 88-174 MHz

    • Cell: 850-1900 MHz

What size mesh do you need

What Size Mesh Do You Need?

  • Mesh size 1/10 the wavelength

Activity building a faraday cage

Activity: Building a Faraday Cage

  • Remove foil from top of box lid.

  • Cut several ½” strips of foil.

  • Make a grid of strips on the lid.

  • Experiment with size openings until a phone will not ring in box.

Data analysis and conclusions

Data Analysis and Conclusions

  • When using aluminum strips, what size openings worked to stop the radio? A cell phone?

  • Why does the opening size matter in a Faraday Cage?

  • What other materials could be used?

Wavelength matters

Wavelength Matters

  • Locations where wireless equipment does not work

  • Protection from electronic spies

  • Space weather effects

  • EMP

Thank you

Thank You!

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