Oscillations and Waves > Waves > Standing Waves DCS# 5N10.57
STANDING WAVES IN A MICROWAVE OVEN
APPARATUS
microwave oven
 N002-02-D
neon bulb array with feet
 202-13-A2
styrofoam cup filled with water
 202-04-A
video camera, if necessary
 202-09-D

DESCRIPTION
The array can be oriented horizontally or vertically in the oven.  Set the oven on high and run for no more than 30 seconds; less if you don't use the turntable.  The electric field produces patterns in the neon bulb array.

This applet from falstad.com depicts 3-dimensional standing wave modes for electromagnetic waves in a box:  http://www.falstad.com/embox/.  Given the wavelength (12.2 cm) and cavity dimensions (36 x 36 x 24 cm) for our oven, the (3, 4, 2) and (4, 3, 2) TE modes satisfy the standing wave conditions, ignoring the effect of the cup of water.

NOTE

Place a cup of water or two in the oven as load to protect the magnetron.

REFERENCE

2004 Phys. Educ. 39 74