# If the characteristics equation of a closed loop system is s2+2s+2=0, then the system is...

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If the characteristics equation of a closed loop system is s2+2s+2=0, then the system is

(A) Over damped (B) Critically damped (C) Under damped (D) Undamped

C.

Solving the above character equation gives complex roots -1+i and -1-i. If we plot that roots on real and imaginary axis plane(s-plane), it will be completely on left side of s-plane. So, the oscillations of the above conjugate roots are underdamped and are absolutely stable.

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