1. 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
✅ The correct answer is option B.
Passive Filters MCQs
2. 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
✅ The correct answer is option D.
3. 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
✅ The correct answer is option C.
4. An RL low-pass filter consists of a 5.6 mH coil and a 3.3 kΩ resistor. The output voltage is taken across the resistor. The circuit’s critical frequency is______________?
A. 93.8 kHz
B. 93.8 Hz
C. 861 Hz
D. 86.12 kHz
✅ The correct answer is option A.
5. At a certain frequency, the output voltage of a filter is 6 V and the input is 12 V.the filter’s bandwidth is____________?
A. 530 Hz
B. 106 Hz
C. 11.5 Hz
D. 53 Hz
✅ The correct answer is option D.
6. A parallel resonant band-pass filter consists of a 6.8 Ω resistor in series with a parallel network made up of an 8 µH coil and a 120 pF capacitor. The output is taken across the capacitor/coil. Assume RW = 0 Ω. What is the center frequency of the filter?
A. 5.14 MHz
B. 514 kHz
C. 5.03 MHz
D. 503 kHz
✅ The correct answer is option A.
7. 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
✅ The correct answer is option A.
8. A series resonant band-stop filter consists of a 68 Ω resistor, a 110 mH coil, and a 0.02 µF capacitor. The internal resistance, RW, of the coil is 4 Ω. Input voltage is 200 mV. Output voltage is taken across the coil and capacitor in series. What is the output voltage magnitude at f0?
A. 1.1 mV
B. 11.1 mV
C. 111 mV
D. 200 mV
✅ The correct answer is option B.
9. Vout = 500 mV, and Vin = 1.3 V. The ratio Vout/ Vin expressed in dB is__________?
A. 0 dB
B. 8.30 dB
C. -8.30 dB
D. 0.8 dB
✅ The correct answer is option C.
10. 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
✅ The correct answer is option B.