Homework Set 1 for Modern Physics - Fall 2006 | PHYSICS 390, Assignments of Physics

Download Homework Set 1 for Modern Physics - Fall 2006 | PHYSICS 390 and more Assignments Physics in PDF only on Docsity! Physics 390: Homework set #1 Due Wednesday January 18, 2006 Reading: Tipler & Llewellyn, Chapter 3 Questions: 1. Show that the classical wave equation ∂2f ∂t2 − c2∂ 2f ∂x2 = 0 is satisfied by any function f that depends on x and t in the combination u = x ± ct: f(x, t) = f(u) = f(x± ct). 2. Planck’s constant is h = 6.626× 10−34 J·s. What familiar physical quantity from classical mechanics also has dimensions of J·s? 3. In what region of the electromagnetic spectrum does the blackbody radiation from a roomtemperature object peak? What sorts of problems would we have if our eyes were sensi- tive in this region? 4. The Compton scattering formula suggests that objects viewed from different angles should reflect light of different wavelengths. Why don’t we observe a change in color of objects as we change the viewing angle? Problems: 3, 141, 30, 36, 45, 49, 54 1Hint: the total energy density is U = ∫∞ 0 u(λ)dλ = ∫∞ 0 u(f)df . Remember to consider the effect of transforming the integration variable from λ to f . 1