GATE Electrical Engineering - Complete Master Library

 

GATE Electrical – Analog Electronics

Practice Problems – Page 17

This section contains problems based on Active Filters using Operational Amplifiers.

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Problem 161

Question:

What is a low pass filter?

Answer:

A low pass filter allows low frequency signals to pass and attenuates high frequency signals.

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Problem 162

Question:

What is a high pass filter?

Answer:

A high pass filter allows high frequency signals to pass and blocks low frequency signals.

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Problem 163

Question:

Write the cut-off frequency formula of an RC filter.

Answer:

fc = 1 / (2πRC)

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Problem 164

Question:

If R = 10 kΩ and C = 0.01 μF, find the cut-off frequency.

Solution:

fc = 1 / (2πRC)

RC = 10,000 × 0.01 × 10⁻⁶

fc ≈ 1591 Hz

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Problem 165

Question:

What is a band pass filter?

Answer:

A band pass filter allows signals within a certain frequency range to pass.

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Problem 166

Question:

What is a band stop filter?

Answer:

It blocks a specific band of frequencies while allowing others to pass.

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Problem 167

Question:

Why are active filters preferred over passive filters?

Answer:

Because they provide amplification and better frequency control.

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Problem 168

Question:

Which component in a filter determines cut-off frequency?

Answer:

Resistor and Capacitor

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Problem 169

Question:

What is the slope of a first order filter?

Answer:

−20 dB/decade

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Problem 170

Question:

What is the slope of a second order filter?

Answer:

−40 dB/decade