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Sketch the asymptotic Bode plots of the magnitude and phase for H(s) = 80s/(s + 10)(s + 20)(s + 40), s = jω.

User Iksnae
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Final answer:

Bode plots are used to represent the frequency response of a system. For the given transfer function H(s), the magnitude plot combines the initial positive slope with negative contributions from each pole, while the phase plot shifts downward at each pole. These are asymptotic approximations, and precise plotting would demand more detailed analysis.

Step-by-step explanation:

The question asks to sketch the asymptotic Bode plots for the magnitude and phase of a given transfer function, H(s) = 80s/(s + 10)(s + 20)(s + 40), where s = jω. Bode plots are graphical representations of a system's frequency response and are commonly used in control systems and signal processing to analyze the behavior of linear time-invariant systems.

To create Bode plots, one typically separates the transfer function into its component parts, each contributing a slope to the overall plot. For the magnitude plot, the slope starts at +20 dB/decade due to the 's' in the numerator and then decreases by -20 dB/decade at each pole of the transfer function, which occurs at frequencies of 10 Hz, 20 Hz, and 40 Hz. The phase plot typically starts at zero degrees and changes by -90 degrees at each pole, since we have a first-order system in the numerator and three first-order systems in the denominator.

Remember that these Bode plots are asymptotic and approximate the actual response; exact plotting requires more detailed calculations or the use of computational tools. Control systems often require precise analysis and design to ensure system stability and desired performance.

User Justin Bull
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