Transmitted Waves - Vibrations and Waves - Past Exam, Exams of Physics

Download Transmitted Waves - Vibrations and Waves - Past Exam and more Exams Physics in PDF only on Docsity! Physics 171.201 Midterm Exam 2 November 10th, 2004 Answer all three problems. Be sure that you pace yourself so that you have enough time to work on each problem. Note that the problems do not have equal weight. Partial credit will be given, so be sure to show your work as clearly as possible. Good luck! Problem 1 (30 points) Two very long segments of string are joined at x = 0 as shown. The segment for x < 0 has a mass per unit length of r1 = 0.16 kilograms/meter, and the segment for x > 0 has r2 = 0.25 kilograms/meter. The entire string is under a uniform tension T0 = 100 N. Suppose a transverse traveling wave described by y(x,t) = Acos(wt – kx) is incident on the boundary (x = 0) from the left with amplitude A = 1 meter and frequency w = 10 radians/second. (a) Calculate the amplitudes of the reflected and transmitted waves. (b) What is the frequency and wavelength of the transmitted wave? (c) What fraction of the energy of the incident wave gets transmitted? x = 0 r1 r2