Updated September 2011 Measuring Resolution with Marshmallows Experiment

Updated September 2011 Why does food cook unevenly in a microwave? Background cc by Niels Heidenreich

Updated September 2011 Microwaves are electromagnetic waves cc by Lenny222

Updated September 2011 Microwaves work by causing the water, sugar, and fat in food to absorb energy. Image by Baran Ivo

Updated September 2011 Data Analysis We can determine the frequency of a microwave by measuring the “energy nodes”. We will do this by heating marshmallows. Follow the procedure on your worksheet. Record your results.

Updated September 2011 Data Analysis Compare the energy antinodes in the marshmallows to the airy patterns and limits of resolution for a light microscope Image from MicroscopyU

Updated September 2011 Data Analysis cc by Inductiveload Electromagnetic radiation covers a huge range of wavelengths. Light (the part of the electromagnetic spectrum that we can detect with our eyes) is only a small portion of this range. X- rays, light, and microwaves are all examples of electromagnetic waves. On the electromagnetic spectrum chart: 1.Locate visible energy wavelengths. What is the resolution limit? 2. Locate microwave energy wavelengths. What is the resolution limit? 3. What energy source emits nanoscale wavelengths? What measurement resolution is required? 4. How much smaller are nanoscale wavelengths compared to microwave wavelengths? (ratio)

Updated September 2011 This module is one of a series designed to introduce faculty and high school students to the basic concepts of nanotechnology. Each module includes a PowerPoint presentation, discussion questions, and hands-on activities, when applicable. The series was funded in part by: The National Science Foundation Grant DUE and the Oklahoma Nanotechnology Education Initiative Any opinions, findings and conclusions or recommendations expressed in the material are those of the author and do not necessarily reflect the views of the National Science Foundation or the Oklahoma Nanotechnology Education Initiative.

Updated September 2011 Image Credits Heidenreich, Neil. (Photographer) Croissant Fatality. Flickr. ( Microscopy U. (Designer). Airy Patterns and the Limit of Resolution. ( Inductiveload. (Designer). EM Spectrum Properties. Wikimedia Commons. (commons.wikimedia.org) Ivo, Baran. (Photographer). Microwave Oven. Wikimedia Commons. (commons.wikimedia.org)

Updated September 2011 References Davidson, Michael. Microscopy Basics: Resolution. Microscopy U. Retrieved from Goldman, Martin V. Microwaves [Online Applet Lesson]. Physics Retrieved from Stauffer, Robert H. Finding the Speed of Light with Marshmallows-A Take-Home Lab (1997). The Physics Teacher. Vol. 35, April p