Amplifier Frequency Response Questions and Answers
Amplifier Frequency Response questions with answers help students understand how amplifiers behave across different frequencies. This topic is essential in electronics aptitude questions and answers with explanations, especially for competitive exams like GATE, ISRO, DRDO, and ECIL. The frequency response defines the amplifier’s ability to amplify signals within a specific frequency range while maintaining consistent gain. Understanding this helps in designing stable electronic circuits and predicting their performance in real-world applications. By practicing aptitude test questions with solutions PDF or online, learners can strengthen their knowledge of bandwidth, gain roll-off, and frequency characteristics, which are critical in both academic and placement tests.
Amplifier Frequency Response
1. Doubling the voltage gain causes a ________ dB ________.
- 10, increase
- 6, increase
- 10, decrease
- 6, decrease
2. ________ frequencies are values of frequency at which the RC circuits reduce the voltage gain to 70.7% of its midrange value.
- Critical
- Cutoff
- Corner
- all of the above
3. A roll-off of 20 dB per decade is equivalent to a roll-off of ________ per octave.
- 3 dB
- 13 dB
- 12 dB
- 6 dB
4. Each RC circuit causes the gain to drop at a rate of ________ dB/decade.
- 20
- 10
- 6
- none of the above
5. The phase shift through the input of an RC circuit approaches ________° as the frequency approaches zero.
- 0
- 45
- 180
- 90
6. A certain amplifier has a bandwidth of 22.5 kHz with a lower cutoff frequency of 600 Hz. What is the value of fcu?
- 600 Hz
- 22.5 kHz
- 23.1 kHz
- 21.9 kHz
7. Internal transistor junction capacitances affect the high-frequency response of amplifiers by
- reducing the amplifier's gain.
- introducing phase shift as the signal frequency increases.
- having no effect.
- reducing the amplifier's gain and introducing phase shift as the signal frequency increases.
8. What is the method that can be used to determine the values of fcl and fcu of an amplifier?
- five time constants
- step-response
- sinusoidal
9. An amplifier has an input signal voltage of 0.054 mV. The output voltage is 12.5 V. The voltage gain in dB is
- 53.6 dB.
- 107.3 dB.
- 231 dB.
- 116 dB.
10. The lower critical frequency is also known as the
- break frequency.
- cutoff frequency.
- corner frequency.
- all of the above