Find the low-frequency (DC) gain of G(s) = 3100(s + 15)/((s + 1)(s + 80)) in decibels, |G(0)| in dB.
Bode plots & margins worksheet with answers
Find the corner (−3 dB) frequency ωc of the RC low-pass filter shown, with R = 4.7 kΩ, C = 47 nF. Give it in rad/s.
The RC high-pass filter shown has R = 10 kΩ, C = 22 nF. A sinusoidal input of 2.9 kHz is applied. Find the phase shift φ of vout relative to vin, in degrees.
The RC low-pass filter shown has R = 10 kΩ, C = 100 nF. A sinusoidal input of 80 Hz is applied. Find the phase shift φ of vout relative to vin, in degrees.
A unity-feedback loop has the open-loop transfer function L(s) = 35/(s(s + 2)). Find the gain crossover frequency ωc, where |L(jω)| = 1.
A unity-feedback loop has the open-loop transfer function L(s) = 10/(s(s + 1)(s + 3)). Find the phase crossover frequency ω180, where ∠L(jω) = −180°.
Answer key
- 1. |G(0)| = 55.29 dB
- 2. ωc = 4527 rad/s
- 3. φ = 14.01 °
- 4. φ = −26.69 °
- 5. ωc = 5.75 rad/s
- 6. ω180 = 1.732 rad/s
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