Question

On the EM Spectrum, which type of wave has the most energy?

Answer 1

Gamma rays.

Explanation:

A general guideline tends to be : short wavelength, high energy . But here is a way to show which waves are the most energetic:

The energy of a wave is given by the equation:

`E=hf`

`h`=Planck's constant `(6,6261·10^(-34) Js^-1)`
`f`=frequency of the wave

Hence we can see that the energy of a wave is proportional to its frequency, as the other term is a constant.

Then we can ask ourselves, which waves are the ones with the highest frequency?

If we use another equation:

`c=flambda`

`c`=speed of light ,`3.0 times 10^8 ms^-1`
`f`=frequency (Hz)
`lambda`=wavelength in meters.

Then we can see that, as `c` is constant in a vacuum, and `f` is high, then `lambda`, the wavelength, must be low.
Now if we use this diagram of the EM-spectrum which show wavelengths:

We can thus conclude that the waves that have the shortest wavelength are gamma rays, and thus they are the most energetic because they must also have the highest frequency.