24. If you dip your finger repeatedly into a puddle of water, it creates waves. What happens to the wavelength if you dip your finger more frequently?
29. What two physics mistakes occur in a science fiction movie that shows a distant explosion in outer space, where you see and hear the explosion at the same time?
26. Tom Senior makes music by setting small columns of air into vibration by blowing across the ends of drinking straws of various lengths. Which straws, the short ones or the long ones, produce lower pitch? What would you expect of the pitch produced by the much larger musical instrument behind Tom that uses resonant air columns excited by striking the ends of the tubes with paddles?
5. Which has the shorter wavelengths, ultraviolet or infrared? Which has the higher frequencies?
- On a TV screen, red, green, and blue spots of fluorescent materials are illuminated at a variety of relative intensities to produce a full spectrum of colors. What dots are activated to produce yellow? Magenta? White?
7. Why is the lettering on the front of some vehicles “backward”?
Why do radio waves diffract around buildings, while light waves do not?
Ultraviolet light causes sunburns, whereas visible light, even of greater intensity, does not. Why is this so?
Cite at least two reasons for predicting that LEDs will emerge as more popular than CFLs.