iVenky
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Consider a system whose transfer function is given by
T(s)= 1 / (s+ja)(s-ja)
It's very clear that we have a pole at the frequency w=a; Assume that this 'a' is very near to 0. Then you can say this as low pass filter.
Now my question is this-
What will happen when you give a input sine wave with frequency equal to a?
From the low pass filter characteristics you will say that it is approximately equal to the passband gain which is 1 here.
But if you substitute s=ja in the above equation you will get it as infinite.
I am a bit confused with this.
Will you please clear my doubt?
thanks in advance.
T(s)= 1 / (s+ja)(s-ja)
It's very clear that we have a pole at the frequency w=a; Assume that this 'a' is very near to 0. Then you can say this as low pass filter.
Now my question is this-
What will happen when you give a input sine wave with frequency equal to a?
From the low pass filter characteristics you will say that it is approximately equal to the passband gain which is 1 here.
But if you substitute s=ja in the above equation you will get it as infinite.
I am a bit confused with this.
Will you please clear my doubt?
thanks in advance.