Question

1. if an rl filter circuit uses a 1 kω resistor and a 10 mh inductor, what is fco?

a 6.28 khz
b 15.9 khz
c 62.8 khz
d 1 mhz

Explanation:

Step1: Recall the formula for the cutoff frequency of an RL filter

The formula for the cutoff frequency \( f_{co}\) of an RL filter is \( f_{co}=\frac{R}{2\pi L}\).

Step2: Substitute the given values

Given \( R = 1\times10^{3}\ \Omega\) and \( L=10\times 10^{- 3}\ H\).
Substitute into the formula: \( f_{co}=\frac{1\times10^{3}}{2\pi\times10\times 10^{-3}}\).

Step3: Calculate the value

First, simplify the denominator \( 2\pi\times10\times 10^{-3}=2\pi\times10^{-2}\).
Then \( f_{co}=\frac{1\times10^{3}}{2\pi\times10^{-2}}=\frac{1\times10^{5}}{2\pi}\).
Since \(\pi\approx3.14\), \( f_{co}=\frac{1\times10^{5}}{2\times3.14}\approx15923.57\ Hz\approx15.9\ kHz\).

Answer:

B. 15.9 kHz