Electrical Wave Filters Questions and Answers

Electrical Wave Filters Questions and Answers

Q1. What are the commonly used filters?

The most commonly used filters are low-pass, high-pass band-pass, band-reject and all-pass filters.

Q2. What is the difference between active and passive filters?

A passive filter is formed with passive components, such as resistors, inductors and capacitors while active filters make use of transistors or op-amps in addition to resistors and capacitors.

Q3. Why are active filters preferred

Active filters are preferred over passive filters because they provide gain and frequency adjustment flexibility. They pose no loading problem because of high input impedance and low output impedance and they are comparatively less expensive.

Q4. What is a low-pass filter?

A filter that provides a constant output from dc upto a cutoff frequency fC and then passes no signal above that frequency is called a low-pass filter.

Q5. What is a high-pass filter?

A filter that provides or passes signals above a cutoff frequency fCis called a high-pass filter. It has a zero gain starting from zero to a frequency fC and above this frequency the gain is constant.