1B.15


Moderators: Chem_Mod, Chem_Admin

Ricky Ma DIS 4E
Posts: 72
Joined: Fri Sep 28, 2018 12:27 am

1B.15

Postby Ricky Ma DIS 4E » Mon Oct 15, 2018 7:26 pm

The velocity of an electron that is emitted from a metallic surface by a photon is 3.6 x10^3km/s
(a) What is the wavelength of the ejected electron?

I understand now that you use the Debroglie equation. My problem is that I tried using the Ek=0.5mv^2 first then using lambda=hc/E to find the wavelength but I couldn't get the right answer. Is there a reason that that method does not work? I first turned the 3.6 x10^3km/s into meters then just plugged that into the "v" of Ek=0.5mv^2 but ended up with the wrong answer.

Thanks!

Michael Torres 4I
Posts: 92
Joined: Thu May 10, 2018 3:00 am
Been upvoted: 1 time

Re: 1B.15

Postby Michael Torres 4I » Mon Oct 15, 2018 8:42 pm

The problem with using (lambda) = hc/E in this case is that it can only be applied to light or something without rest mass. Because the electron has rest mass, DeBroglie's equation must be used.

(lambda) = hc/E can be used to find the wavelengths of electromagnetic radiation, whereas DeBroglie's equation can be applied to objects with rest mass.


Return to “DeBroglie Equation”

Who is online

Users browsing this forum: No registered users and 2 guests