A system has a complex conjugate root pair of multiplicity two or more...
Answer: c
Explanation: Poles are the roots of the denominator of the transfer function and on imaginary axis makes the system stable but multiple poles makes the system unstable.
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A system has a complex conjugate root pair of multiplicity two or more...
The impulse response of a system can provide valuable information about its behavior and stability. In this case, we are given that the system has a complex conjugate root pair of multiplicity two or more in its characteristic equation. Let's analyze the implications of this on the system's impulse response.
Complex Conjugate Root Pair
A complex conjugate root pair in the characteristic equation of a system indicates the presence of oscillatory behavior in the system's response. Complex conjugate roots are of the form a ± bi, where a and b are real numbers and i is the imaginary unit (√-1). These roots give rise to sinusoidal terms in the impulse response.
Multiplicity Two or More
The multiplicity of a root refers to the number of times it appears in the characteristic equation. When a complex conjugate root has a multiplicity of two or more, it means that it appears multiple times in the equation. This results in an exponential rise or decay in the sinusoidal terms of the impulse response.
Implications on the Impulse Response
Based on the given information, the impulse response of the system will exhibit the following characteristics:
1. Sinusoidal Oscillation: The presence of a complex conjugate root pair indicates the occurrence of sinusoidal terms in the impulse response. These sinusoids represent the oscillatory behavior of the system.
2. Exponential Rise: Since the complex conjugate root pair has a multiplicity of two or more, the sinusoidal terms in the impulse response will experience exponential rise. This means that the amplitude of the oscillation will increase over time.
3. Unstable System: An exponentially rising sinusoidal term indicates an unstable system. As the amplitude continuously grows, the system's response becomes unbounded and uncontrollable. This behavior is undesirable in most engineering applications.
Conclusion
In summary, a system with a complex conjugate root pair of multiplicity two or more in its characteristic equation will have an impulse response that exhibits a sinusoidal oscillation with exponential rise. This behavior indicates an unstable system, as the response grows without bound.