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PHY 7 11 Classical Mechanics and Mathematical Methods 9-9:50 AM MWF Olin 107 Plan for Lecture 26: Motions of elastic membranes (Chap. 8) Review of standing waves on a string Standing waves on a two dimensional membrane. Boundary value problems. Elastic media in two or more dimensions --.
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PHY 711 Classical Mechanics and Mathematical Methods • 9-9:50 AM MWF Olin 107 • Plan for Lecture 26: • Motions of elastic membranes (Chap. 8) • Review of standing waves on a string • Standing waves on a two dimensional membrane. • Boundary value problems PHY 711 Fall 2017 -- Lecture 26
Elastic media in two or more dimensions -- Review of wave equation in one-dimension – here m(x,t) can describe either a longitudinal or transverse wave. Traveling wave solutions -- PHY 711 Fall 2017 -- Lecture 26
Standing wave solutions of wave equation: PHY 711 Fall 2017 -- Lecture 26
Wave motion on a two-dimensional surface – elastic membrane (transverse wave; linear regime). u(x,y,t) PHY 711 Fall 2017 -- Lecture 26
Consider a rectangular boundary: b a PHY 711 Fall 2017 -- Lecture 26
More general boundary conditions: PHY 711 Fall 2017 -- Lecture 26
Consider a circular boundary: R PHY 711 Fall 2017 -- Lecture 26
Consider circular boundary -- continued PHY 711 Fall 2017 -- Lecture 26
Some properties of Bessel functions PHY 711 Fall 2017 -- Lecture 26
http://dlmf.nist.gov/ PHY 711 Fall 2017 -- Lecture 26
Series expansions of Bessel and Neumann functions PHY 711 Fall 2017 -- Lecture 26
Some properties of Bessel functions -- continued PHY 711 Fall 2017 -- Lecture 26
More complicated geometry – annular membrane a b PHY 711 Fall 2017 -- Lecture 26
Consider circular boundary -- continued PHY 711 Fall 2017 -- Lecture 26
Normal modes of an annular membrane -- continued a b PHY 711 Fall 2017 -- Lecture 26
Normal modes of an annular membrane -- continued a b PHY 711 Fall 2017 -- Lecture 26
Normal modes of an annular membrane -- continued a b PHY 711 Fall 2017 -- Lecture 26
Analysis for m=0 and a=0.1, b=0.2: PHY 711 Fall 2017 -- Lecture 26
a b PHY 711 Fall 2017 -- Lecture 26