To summarise, the gain and phase shift of a Passive Low-Pass filter are:
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				$|H|={1 \over {\sqrt{1+(\omega RC)^2}}}$ 
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				$\phi = -tan^{-1} (\omega RC)$
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				The cut-off frequency of the filter is:
				<br>
				$\omega_c = {1 \over RC}$
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				The graph above shows the input and output signals of a Passive Low-Pass filter with a cut-off frequency of 1Hz.
				Use the slider to adjust the input frequency.