00:01
Find the bandwidth and center frequency of the band stop filter and the figure is referring to the figure the capacitance is written as 1 by sc and for the inductance written by sl the combination at the output is the inductor and the capacitor which is in series this can be written as r into sl plus 1 by sc divided by r plus sl plus 1 by sc.
00:33
Here s is equals j omega.
00:36
We can write this impedance as r into 1 plus s square lc by 1 plus src plus s square lc.
00:47
Determining the transfer function h s equals v0s by vis substituting here the output voltage is the load impedance at the output by load impedance at output plus r0.
01:09
We can substitute the value here r into 1 plus s square lc by r0 plus s r r not plus s square lc plus s square lc r plus r plus s square lc r.
01:29
Substituting s equals to j omega here, then the transfer function in terms of j omega will be r into 1 plus j omega whole square lc by r not plus j omega into r r not c plus j omega whole square lc r c r r not plus r plus j omega whole square l c r plus the equivalent impedance of the circuit r not plus z s this is equals to r not plus z s this is equals to r not plus z s value is into 1 plus s square lc by 1 plus src plus s square lc the equivalent impedance will be r not plus s r not r c plus s square r not lc plus r plus r s square lc plus r s square lc whole divided by 1 plus src plus s square lc.
02:49
Substituting as equals to j omega here into this equation, z -in will be r0 plus r -c minus omega square l -c r -cr -r -c -r -plus j -o -mega -r -n -c, multiply 1 minus omega -square l -c minus j -o -mega -r -c.
03:17
This is divided by 1 -1 -1 -1 -omega -square -l -c, whole square plus omega r c whole square.
03:27
To determine the center frequency, the imaginary part of the impedance must be zero, therefore substituting r0 plus r not minus omega square lc r0 minus omega square lc r not minus r0 plus omega square r0lc equals 0.
03:55
From here the value 4, omega comes out to be 1 by root lc...