1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

What is the energy of one of the orange light photons?

  1. Jan 15, 2006 #1
    The Argon gas laser produces orange light of wavelength 6.3E-7 meters and of frequency 4.76E14 Hz. The laser output is 5.2 mW
    a. What is the energy of one of the orange light photons?
    b. What is the momentum of one of the orange light photons?
    c. How many photons per second does this laser emit?
    d. What is the realtionship between (c) and the frequency of the light
     
  2. jcsd
  3. Jan 15, 2006 #2
    a. the energy of a photon is hf.
    b.
    from special relativity [tex]E^2=m^2c^4+p^2c^2[/tex]
    since the rest mass of a photon is zero, it becomes [tex]E=pc[/tex]
    so, [tex]p = \frac{E}{c}[/tex]
    since [tex]E = hf = h (\frac{c}{\lambda})[/tex],
    [tex]p = (\frac{hc}{\lambda}) *(\frac{1}{c})[/tex]
    [tex]p = \frac{h}{\lambda} [/tex]
    c. okay, you know the energy per second the laser emmits right?
    how many times the energy of a single photon is it?
    d. whats the relation between f and c? (hint: you can find it on this post...)
     
    Last edited: Jan 15, 2006
  4. Jan 15, 2006 #3
    a 6.6E-34(4.76E14)
    =3.14E-19
    b p=6.6E-34/6.3E-7
    =1.05E-27
    c 5.2E-4/3.14E-19
    =1.66E15
    d ...i cant see a relation between
    1.66E15 photons per second
    and 4.76E14 Hz
    unless i did something wrong
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: What is the energy of one of the orange light photons?
Loading...