IN two recent notes 1, we reported that ultrasonic waves of frequencies as high as 100 Mc./sec. were generated. The diffraction patterns produced by such waves were found to exhibit interesting ...

Explores the principles of light, reflection, and magnification through hands-on experiments. Children observe how a magnifying glass focuses sunlight to create heat, examine the effects of light on ...

USING a specially constructed rectifier giving 1,100 volts and a Taylor T 55 valve with amphenol bases and special inductances, frequencies up to 100 megacycles per second have been produced. A ...