Physics: Principles with Applications (7th Edition)

Published by Pearson
ISBN 10: 0-32162-592-7
ISBN 13: 978-0-32162-592-2

Chapter 28 - Quantum Mechanics of Atoms - Problems - Page 827: 33

Answer

Shortest: $4.35\times10^{-2}nm$ Longest: ~ 1 nm

Work Step by Step

The smallest wavelength X-ray has the most energy. The incoming electrons have an energy of 28.5 keV, so that is the maximum energy of an x-ray photon. In this problem, the value of hc is useful. Use the result stated in Chapter 27, Problem 29, $hc=1240\;eV \cdot nm$. Use equation 27–4, E = hf, and recall that $\lambda f = c$. $$\lambda = \frac{c}{f}=\frac{hc}{hf}=\frac{1240\;eV \cdot nm }{28500eV}=4.35\times10^{-2}nm$$ The longest wavelength (lowest energy) photon is at the boundary of what is considered to be the x-ray region, approximately 1 nm.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.