Which filter type attenuates a specific middle-frequency band while allowing high and low frequencies to pass?

Which filter type attenuates a specific middle-frequency band while allowing high and low frequencies to pass?

• A. Band-reject
• B. Band-pass
• C. Solid-state
• D. Three-phase Rectifier

Answer: (A)

A filter that attenuates a specific middle-frequency band while letting low and high frequencies pass is a band-stop (band-reject) filter. Its frequency response has a notch or dip around a center frequency, significantly reducing those midband components while the signal components outside that band pass through with little attenuation. This is why it’s used to remove a narrow band of interference or unwanted tones without affecting the overall low- and high-frequency content. By contrast, a band-pass filter would do the opposite, passing only the middle frequencies and attenuating the rest, and the other two options are not filter types: solid-state refers to a type of semiconductor-based device, and a three-phase rectifier is a power-conversion component, not a frequency-selective filter.

A filter that attenuates a specific middle-frequency band while letting low and high frequencies pass is a band-stop (band-reject) filter. Its frequency response has a notch or dip around a center frequency, significantly reducing those midband components while the signal components outside that band pass through with little attenuation. This is why it’s used to remove a narrow band of interference or unwanted tones without affecting the overall low- and high-frequency content.

By contrast, a band-pass filter would do the opposite, passing only the middle frequencies and attenuating the rest, and the other two options are not filter types: solid-state refers to a type of semiconductor-based device, and a three-phase rectifier is a power-conversion component, not a frequency-selective filter.