Stability Theory » Exercise – 2
51. The parameter which is constant along the constant N circle is :
(a) frequency
(b) phase angle
(c) magnitude
(d) open-loop gain
52. If the s-plane contour encloses 2 zeros and 2 poles of q(s), the corresponding q(s) plane contour will encircle the origin of q(s) plane :
(a) twice in clockwise direction
(b) twice in counterclockwise direction
(c) zero times
(d) four times
53. The phase margin of a system is 40˚. The damping ratio of the system ξ is approximately :
(a) 0.04
(b) 0.4
(c) 4
(d) cannot be estimated
54. The damping ratio of a second-order system is 0.2. Its phase margin is approximately :
(a) 0.4˚
(b) 2˚
(c) 20˚
(d) 40˚
55. A polar plot crosses the real axis at (-1 + j0) point. The gain margin of the system is :
(a) -1˚
(b) 0˚
(c) -180˚
(d) +180˚
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Stability Theory » Exercise - 252. If the s-plane contour encloses 2 zeros and 2 poles of q(s), the corresponding q(s) plane contour will encircle the origin of q(s) plane : (a) twice in clockwise direction (b) twice in counterclockwise direction (c) zero times (d) four times- Stability Theory » Exercise - 258. If the s-plane contour encloses 3 poles and 2 zeros of q(s), the corresponding q(s) plane contour will encircle the origin of q(s) plane : (a) once in clockwise direction (b) once in counterclockwise direction (c) thrice in clockwise direction (d) twice in counterclockwise direction
- Stability Theory » Exercise - 266. If the s-plane contour encloses 3 zeros and 2 poles of q(s), the corresponding q(s) plane contour will encircle the origin of q(s) plane : (a) once in clockwise direction (b) once in counterclockwise direction (c) thrice in clockwise direction (d) twice in counterclockwise direction
- Stability Theory » Exercise - 255. A polar plot crosses the real axis at (-1 + j0) point. The gain margin of the system is : (a) -1˚ (b) 0˚ (c) -180˚ (d) +180˚
- Stability Theory » Exercise - 265. A polar plot intersects the unit circle at a point making an angle of -45 ˚ with the negative real axis. The phase margin of the system is : (a) -45˚ (b) 45˚ (c) -180˚ - 45˚ (d) -180˚ + 45˚