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ask_LXXXVI
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Here's a scenario about which I have doubt. Consider a transmission line which has a length λ/4 and which has open circuit at load end. The source resistance is zero. The source voltage be Vs and the source frequency is sufficiently high to be considered as high frequency application . The line is perfectly loss-less (sorry for considering an ideal situation, I just am asking this to clear my basic concepts). My question is what will be the voltage standing wave patterns on the line ?
Now as we know the open circuit at load end will give us ΓL (which is reflection coefficient at load end) = 1. So the voltage standing wave has voltage maxima , Vmax = 2|V+| and voltage minima , Vmin= 0 . where |V+| is the magnitude of the forward traveling wave. But interestingly in this scenario the voltage maxima occurs at load end and thus the voltage minima occurs at source end (as the length is λ/4) . So because of this Vmin can't be zero but equals a finite quantity i.e the source voltage Vs . Also this leads to Vmax and |V+|being equal to infinite . So my doubt is what would be the voltage at other points on the standing wave. I personally think it is infinite at all pts except at the source end where it is Vs.
Please click on image to see it in original size
I tried to simulate the situation on this http://www.amanogawa.com/archive/StandingWavePattern1/StandingWavePattern1-2.html" [Broken] but since it can't deal with infinities my doubt remained unsolved.On the applet ,|V+| I got was a very large number instead of getting infinity.
Now as we know the open circuit at load end will give us ΓL (which is reflection coefficient at load end) = 1. So the voltage standing wave has voltage maxima , Vmax = 2|V+| and voltage minima , Vmin= 0 . where |V+| is the magnitude of the forward traveling wave. But interestingly in this scenario the voltage maxima occurs at load end and thus the voltage minima occurs at source end (as the length is λ/4) . So because of this Vmin can't be zero but equals a finite quantity i.e the source voltage Vs . Also this leads to Vmax and |V+|being equal to infinite . So my doubt is what would be the voltage at other points on the standing wave. I personally think it is infinite at all pts except at the source end where it is Vs.
Please click on image to see it in original size
I tried to simulate the situation on this http://www.amanogawa.com/archive/StandingWavePattern1/StandingWavePattern1-2.html" [Broken] but since it can't deal with infinities my doubt remained unsolved.On the applet ,|V+| I got was a very large number instead of getting infinity.
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