Question

compare 990 on the am dial to 92.3 on the fm. which has the longer wavelength?
the am station.
the fm station.
both stations have the same wavelength.

Explanation:

AM radio waves have lower frequencies than FM radio waves. Using the formula \( c = \lambda f \) (where \( c \) is the speed of light, \( \lambda \) is wavelength, and \( f \) is frequency), when \( c \) is constant (\( c = 3\times10^{8}\ m/s\)), wavelength \( \lambda \) is inversely proportional to frequency \( f \) (\( \lambda=\frac{c}{f} \)). A lower - frequency wave has a longer wavelength. The AM station (990 kHz, since AM frequencies are in the kilohertz range) has a lower frequency than the FM station (92.3 MHz, since FM frequencies are in the megahertz range).

Answer:

The AM station.