A. 1.1 mV

**B. 11.1 mV**

C. 111 mV

D. 200 mV

# Passive Filters

## The maximum output voltage of a certain low-pass filter is 15 V. The output voltage at the critical frequency is_____________?

**A. 10.60 V**

B. 0 V

C. 21.21 V

D. 15 V

## At a certain frequency, the output voltage of a filter is 6 V and the input is 12 V. The voltage ratio in decibels is_____________?

A. 6.02 dB

**B. -6.02 dB**

C. 12.04 dB

D. -12.04 dB

## A series resonant band-pass filter consists of a 2 mH coil, a 0.005 µF capacitor, and a 120 Ω resistor. The winding resistance of the coil is 12 Ω. The output voltage is taken off the resistor. Input voltage is 12 Vrms. What is the output voltage magnitude at the center frequency (f0)?

**A. 10.9 V**

B. 1.09 V

C. 1.1 V

D. 12 V

## An RC high-pass filter consists of a 0.2 µF capacitor and a 220 Ω resistor. The output is taken across the resistor. The circuit’s critical frequency is_____________?

A. 723 Hz

B. 7,234 Hz

C. 362 Hz

**D. 3,617 Hz**

## A parallel resonant band-pass filter consists of a 90 Ω resistor in series with a parallel network made up of a 60 mH coil and a 0.02 µF capacitor. The output is taken across the capacitor/coil. The coil winding has a resistance of 20 Ω. What is the center frequency of the filter?

A. 459 Hz

**B. 4,591 Hz**

C. 999 Hz

D. 2,176 Hz

## In a series resonant band-pass filter, a lower value of Q results in______________?

A. a higher impedance

B. a smaller bandwidth

C. a higher resonant frequency

**D. a larger bandwidth**

## In a certain low-pass filter, fc = 3.5 kHz. Its passband is____________?

A. 3.5 kHz

B. 0 Hz

**C. 0 Hz to 3.5 kHz**

D. 7 kHz

## An RC low-pass filter consists of a 120 Ω resistor and a 0.002 µF capacitor. The output is taken across the capacitor. The circuit’s critical frequency is___________?

A. 333 kHz

**B. 633 kHz**

C. 331 kHz

D. 60 kHz

## In a certain low-pass filter, fc = 3.5 kHz.if the input voltage is a 6 V sine wave with a dc level of 10 V, what is the output voltage magnitude?

A. 0 V

**B. 5.97 V**

C. 6 V

D. 597 mV