How can the value of the constant, 1240, in the Duane-Hunt relation be verified?

  • Thread starter Thread starter saiyaex
  • Start date Start date
  • Tags Tags
    Relation
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
Sign up Log in
1 reply · 3K views
saiyaex
Messages
11
Reaction score
0

Homework Statement


Just going over some practice questions, and one of them is:

1. Verify the value of the constant, 1240, in the Duane-Hunt relation.


Homework Equations


E(eV) = 1240/lambda(nm)


The Attempt at a Solution


I know it is used as a quick method in finding how much energy is involved when a molecule absorbs a photon of light. I therefore know how to use it in a question. However, I'm stumped as to verifying the actual value of the constant. Any insight is appreciated!
 
Physics news on Phys.org

Discussion

Look up the definition of Planck's constant, or more specifically what is called the "Planck relation" or the "Planck–Einstein equation". It relates the energy of a photon to the photon's frequency (or wavelength).

A few other things you may need to know.

  • What is the speed of light in a vacuum (in [m/sec])?
  • What is Planck's constant (in [J sec])?
  • If you know the frequency of a photon, what is the photon's wavelength?
  • How many Joules are there in one electron-volt?
  • how many nanometers are there in a meter?