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1 of 10 articles

Passive RC Low Pass Filter

First order LPF, cutoff frequency fc = 1/(2piRC), roll-off.

Darshan N
Updated: 19 March 2026
4 min read

Passive RC Low Pass

Test your ability to apply first-order LPF transfer functions, cutoff frequency calculations, and roll-off characteristics.

Question 1 of 3

Q1.A first-order passive RC low-pass filter has R = 1 kohm and C = 1 uF. At a frequency of 318 Hz, the magnitude of the output voltage relative to the input is approximately:

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