Question

What is the energy of a photon of microwave radiation with a frequency of `3.20 times 10^11` `s^-1`?

Answer 1

`2.12 * 10^(-22)"J"`

Explanation:

All you have to do here is to use the Planck - Einstein relation, which as you know establishes a relationship between the frequency of a photon and the energy it carries

`color(blue)(ul(color(black)(E = h * nu)))`

Here

• `E` is the energy of the photon
• `h` is Planck's constant, equal to `6.626 * 10^(-34)"J s"`
• `nu` is the frequency of the photon

The problem provides you with the frequency of the photon, so just plug this value into the above equation and solve for `E`

`E = 6.626 * 10^(-34)"J" color(red)(cancel(color(black)("s"))) * 3.20 * 10^(11) color(red)(cancel(color(black)("s"^(-1))))`

`color(darkgreen)(ul(color(black)(E = 2.12 * 10^(-22)"J")))`

The answer is rounded to three sig figs.