(Reflected wave) adding voltage / subtracting current

• nomisme
In summary, when dealing with reflections of signals on conducting lines, it is important to consider the Boundary Conditions at the reflecting surface. If the surface is a perfect conductor, the voltage drop must be zero and the currents will adjust accordingly. This explains why we add reflected voltage to the input voltage but subtract current from the input current. Additionally, the reflected current is shown on the other side of the load because it is traveling back to the input source along a different path. The same principle applies to voltage waves, as they also reflect in the same way as current does. This is especially evident in the special cases of an open circuit and a short circuit.
nomisme
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?

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.

1. What is a reflected wave?

A reflected wave is a wave that bounces back after hitting a boundary or obstacle. In the context of electricity, it refers to the behavior of voltage and current when they encounter a change in the medium they are traveling through.

2. How does adding voltage affect a reflected wave?

Adding voltage to a reflected wave will increase its amplitude, or height, but will not change its frequency or wavelength. This means that the wave will appear larger, but will still have the same number of peaks and troughs per unit of time.

3. Why is it important to understand reflected waves in terms of adding voltage?

Understanding how voltage affects a reflected wave is important for designing and troubleshooting electrical systems. It can help determine the appropriate voltage levels to use and identify potential issues, such as impedance mismatches, that may cause reflections.

4. Can voltage be subtracted from a reflected wave?

Technically, yes, voltage can be subtracted from a reflected wave. This would result in a decrease in amplitude, making the wave appear smaller. However, in most practical situations, voltage cannot be directly subtracted from a wave because it is not possible to physically remove voltage from a circuit.

5. How does subtracting current affect a reflected wave?

Subtracting current from a reflected wave will decrease its amplitude, just like subtracting voltage. However, unlike voltage, current can be physically removed from a circuit. By using resistors or other components, current can be "subtracted" from a circuit, which can help reduce reflections and improve the overall performance of the system.

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