ME 441 Exams


Bode Plots (Amplitude)

When finding the transition points on the amplitude plots why do we know that it changes at a certain place? for example how do I know in problem 2 (8-27) that the transition points should be at log(5) and log(1/5). I thought I understood but now I am not seeing where those come from?
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The transition points are related to the break points of the specific term. For the amplitude asymptote it is specifically at the break point, while for the phase plot the transitions occur at log(5*omega_br) and log(omega_br/5)...always. The factor of 5 in the phase asymptotes is always there, and always 5. (It comes from a Taylor series expansion of the actual phase asymptote about omega_br, at which point the phase is 45 degrees.)