(Reflected wave) adding voltage / subtracting current

AI Thread Summary
Reflected voltage is added to the input voltage because it maintains the boundary conditions at the reflecting surface, particularly in cases like open and short circuits. In contrast, reflected current is subtracted from the input current to ensure that the total current remains consistent with the behavior of the load. The reflected current travels back to the input source on a different path due to the nature of wave propagation and the need to satisfy the boundary conditions. Voltage and current waves reflect differently based on these conditions, with voltage reflecting in a way that maintains a zero voltage drop across perfect conductors. Understanding these principles is crucial for analyzing signal behavior in transmission lines.
nomisme
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why we add reflected voltage to the input voltage but subtract current from the input current?

Also why the reflected current is shown on the other side of the load, traveling back to the input source but not on the same path where it travels from?

Does voltage wave reflect the same way as current does?
 
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nomisme said:
why we add reflected voltage to the input voltage but subtract current from the input current?

Also why the reflected current is shown on the other side of the load, traveling back to the input source but not on the same path where it travels from?

Does voltage wave reflect the same way as current does?

It's all to do with the Boundary Conditions at the reflecting surface. If the surface is a perfect conductor, the voltage drop across the surface must be Zero and the currents will 'adjust' to ensure that. This will account for the resulting H field in the reflected wave, I think.
 

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