Question

Would you use a large inductance or a large capacitance in series with a system to filter out low frequencies, such as the 100 Hz hum in a sound system? Explain.

a) Large inductance to filter low frequencies.

b) Large capacitance to filter low frequencies.

c) Large inductance to filter high frequencies.

d) Large capacitance to filter high frequencies.

Answer 1

b) Large capacitance to filter low frequencies. In a filtering application, the choice between using a large inductance or a large capacitance depends on the desired frequency response.

Step-by-step explanation:

b) Large capacitance to filter low frequencies. In a filtering application, the choice between using a large inductance or a large capacitance depends on the desired frequency response. For filtering out low frequencies, such as the 100 Hz hum in a sound system, a large capacitance is more appropriate. The reason lies in the impedance characteristics of these components at different frequencies. The reactance of a capacitor X_C in an AC circuit decreases with increasing frequency X_C = 1/2pi fC. Therefore, at higher frequencies, the capacitor provides lower impedance, effectively allowing those frequencies to pass while blocking lower frequencies. This property makes a large capacitance suitable for filtering out low frequencies.