Question

am waves have a wavelength of approximately 100 meters. fm waves have a wavelength of approximately 1 meter. which one has a higher frequency? which one has higher energy? (1 point)○ am has a higher frequency, but fm is higher energy.○ am has a higher frequency and higher energy.○ fm has a higher frequency and higher energy.○ fm has a higher frequency, but am is higher energy.

Explanation:

Step1: Relate wavelength to frequency

Use the wave speed formula $c = \lambda f$, where $c$ is the speed of light ($3\times10^8$ m/s, constant for electromagnetic waves), $\lambda$ is wavelength, $f$ is frequency. Rearranged: $f = \frac{c}{\lambda}$.

Step2: Compare frequencies

For AM: $\lambda_{AM}=100$ m, so $f_{AM}=\frac{3\times10^8}{100}=3\times10^6$ Hz.
For FM: $\lambda_{FM}=1$ m, so $f_{FM}=\frac{3\times10^8}{1}=3\times10^8$ Hz.
$3\times10^8 > 3\times10^6$, so FM has higher frequency.

Step3: Relate frequency to energy

Use photon energy formula $E = hf$, where $h$ is Planck's constant ($6.626\times10^{-34}$ J·s, constant). Higher $f$ means higher $E$.
Since $f_{FM}>f_{AM}$, $E_{FM}>E_{AM}$.

Answer:

FM has a higher frequency and higher energy.