1. The magnitude-frequency response of a control system is shown in the figure. The value of ω1 and ω2 are respectively :

(a) 10 and 200

(b) 20 and 200

(c) 20 and 400

(d) 100 and 400

2. A system has fourteen poles and two zeros. The slope of its highest frequency asymptote in its magnitude plot is :

(a) – 40 dB/decade

(b) – 240 dB/decade

(c) – 280 dB/decade

(d) – 320 dB/decade

3. The phase angle of the system

varies between :

(a) 0° and 90°

(b) 0° and -90°

(c) 0° and -180°

(d) -90° and -180°

4. The following Bode plot represents :

(a) 100s^{2}/(0.1+0.1s)^{3
}(b) 1000s^{2}/(1+0.1s)^{3
}(c) 100s^{2}/(1+0.1s)^{5
}(d) 1000s^{2}/(1+0.1s)^{5}

5. The open-loop transfer function of a unity feedback control system is 10/(s +5)^{3}. The gain margin of the system will be :

(a) 20 dB

(b) 40 dB

(c) 60 dB

(d) 80 dB