The low pass filter only allows low frequency signals from 0Hz to its cut-off frequency, ƒc point to pass while blocking those any higher.
To create a low pass filter with a frequency cutoff of 1000 Hz, we can use the following formula to determine our capacitor value based on the chosen resistance.
R=47
fc=1000
fc = 1/(2πRC)
So, if
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C=1/(2πRFc) = 1/(
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2π*
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1000*
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47) =
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3.
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3 μF
http://www.learningaboutelectronics.com/Articles/Low-pass-filter-calculator.php#answer1
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