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Note: Items in red are measurements that must be made as you do the experiment.

 

Introduction You will qualitatively and quantitatively explore some properties of electromagnetic waves.  Since the wavelength of microwaves is on the order of centimeters, they prove to be convenient for this experiment.  Specifically, you will see that we generate microwaves that are: are transverse waves. are polarized. are reflected by metal objects. You will also use a microwave antenna to map out the peaks and nodes of a microwave standing wave, in order to measure the wavelength of the microwaves produced by the generator.
Polarization Microwaves are emitted from a generator horn and detected by a small antenna placed at the end of a shaft. (That is, the top of the "T" is the antenna, the bottom of the "T" is the shaft.) If the electric field of the microwaves drives electrons along the length of the antenna, a signal is produced and a voltage is measured on the voltmeter. Rotate the antenna into each of the orientations shown in Figure 1 and observe the reading on the meter. Call the orientations from left to right, "A," "B," and "C." Record the voltages measured for each of these orientations. A voltage:   V B voltage:   V C voltage:   V We can conclude that the microwave is polarized:      Choose one: longitudinally (along the direction of travel) tranverse up and down transverse sideways	Figure 1
Standing Waves Microwaves that are reflected off a sheet of metal back towards their source can interfere with themselves constructively and destructively, thus forming a standing wave pattern (see Figure 2).  Mount the microwave antenna parallel to the microwave polarization direction, place it at a position near the metal sheet and slowly move it to towards the source (but not too close!). The reading on the meter will go up and down as the antenna encounters nodes and antinodes within the standing wave. Record the positions xn  of the first five nodes that you encounter.  Use these measurements to calculate the wavelength and the frequency of the microwaves.  Note that two adjacent nodes are separated by half a wavelength.   Then recall that .
Node 1:  cm Node 2:  cm Node 3:  cm Node 4:  cm Node 5:  cm Wavelength:  cm Frequency:    Hz	Figure 2