A photon has an energy of 2.93 × 10 to the power of -25 J. What is its frequency? What type of electromagnetic radiation is this photon?

Sagot :

You need to know the energy frequency relationship for photons, which is thanks to Max Planck:

Photon Energy = Planck constant x Frequency

Rarranged:
Photon Energy / Planck Constant = Frequency

Planck Constant = 6.63x10^-34

2.93x10^-25 / 6.63x10^-34 = Frequency

Answer: The radiation has a frequency of [tex]4.43\times 10^{9}Hz[/tex] and is a type of radio wave.

Explanation:

The equation given by Planck's follows:

[tex]E=h\nu[/tex]

where,

E = energy of the light  = [tex]2.93\times 10^{-25}J[/tex]

h = Planck's constant  = [tex]6.62\times 10^{-34}Js[/tex]

[tex]\nu[/tex] = frequency of light = ?

Putting values in above equation, we get:

[tex]2.93\times 10^{-25}J=6.62\times 10^{-34}Js\times \nu\\\\\nu=\frac{2.93\times 10^{-25}J}{6.62\times 10^{-34Js}}=4.43\times 10^{9}Hz[/tex]

The relation between frequency and wavelength is given as:

[tex]\nu=\frac{c}{\lambda}[/tex]

where,

c = the speed of light = [tex]3\times 10^8m/s[/tex]

[tex]\nu[/tex] = frequency of radiation = [tex]4.43\times 10^{8}s^{-1}[/tex]

[tex]\lambda[/tex] = wavelength of the radiation = ?

Putting values in above equation, we get:

[tex]4.43\times 10^{8}s^{-1}=\frac{3\times 10^8m/s}{\lambda}\\\\\lambda=\frac{3\times 10^8m/s}{4.43\times 10^8}s^{-1}}=0.677m[/tex]

The radiation having wavelength 0.677 m belongs to radio waves.

Hence, the radiation has a frequency of [tex]4.43\times 10^{9}Hz[/tex] and is a type of radio wave.