Understand how a low pass filter

AI Thread Summary
A low pass filter allows signals with a frequency below a certain cutoff frequency (f_u) to pass while attenuating higher frequencies. The transfer function |H| describes the relationship between output voltage (U_out) and input voltage (U_in), where |H| approaches 1 as frequency (f) approaches 0, indicating maximum output. Conversely, as frequency increases towards infinity, |H| approaches 0, signifying minimal output. Understanding this behavior is crucial for applications like speaker design, where frequency response is essential. Visualizing this relationship through a graph can aid in comprehension of the filter's performance.
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Hi, I'm new into this subject.

I'm trying to understand how a low pass filter (where the frequency f is from 0 Hz to f_u ) for a speacker is working. The fuction for the low pass filter is \mid H \mid = U_out / U_in, that is

\mid H \mid = R / \sqrt{R^2 + ( \omega L )^2}

where

\omega = 2 \pi f

That I don't really understand is how f \rightarrow 0 \Rightarrow \mid H \mid \rightarrow 1 = \mid H \mid_max (f is the frequency) and f \rightarrow \infty \Rightarrow \mid H \mid \rightarrow 0. I believe that I would need a graph.
 
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Gm, I've reckoned it out, I quess it was too persceptible to percieve, sorry.
 
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