Question

A radio wave has a frequency of 4.40 × 108 hz. what is the energy (in j) of one photon of this radiation? enter your answer in scientific notation.

Answer 1

The energy of a single photon is given by
$E=hf$
where 
$h=6.6 \cdot 10^{-34} Js$ is the Planck constant
f is the frequency of the wave (of the photon)

In our problem, the radio wave has a frequency of $f=4.40 \cdot 10^8 Hz$, so if we put this value into the previous formula, we can find the energy of a single photon of this electromagnetic wave:
$E=hf=(6.6 \cdot 10^{-34} Js)(4.40 \cdot 10^8 Hz)=2.9 \cdot 10^{-25} J$