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(e) The wavelength of the transmitted wave is longer than that of the incident wave.
4. In Assignment 3, you learned about two kinds of impedance: the mechanical impedance
of a system, and the characteristic impedance of a medium.
In general, if we drive a mechanical system with a force and measure its response – a
velocity at some position, we can define a mechanical impedance as the ratio of the
complex response to the complex drive, e.g., Z = F/v. In general this will be a function of
the drive frequency.
The characteristic impedance of a medium, on the other hand, characterizes wave
propagation within the medium. For mechanical waves on a string, it relates the force
acting at one end of a string to the velocity of the string at that point, when a single
wave propagating away from that point is present. In other words, it relates the local
force and velocity of the medium associated with a single propagati...
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This note was uploaded on 02/27/2013 for the course PHY 2214 taught by Professor Davis during the Spring '12 term at Cornell.
- Spring '12