How does light travel in a circuit?

Light does not carry energy in a circuit.

What is the role of electrons in a circuit?

Electrons are guided by the electric field in a circuit.

Electric field created by charges pushes charges through.

Poynting vector indicates energy flow direction in circuits.

Transmission lines' impedance affects power delivery.

Electrons do not carry energy from the battery to the bulb in a circuit; instead, it is the electric field created by charges on the battery and wires' surfaces that pushes charges through the circuit.
The Poynting vector in a circuit indicates the direction of energy flow, highlighting that wires are not necessary for energy transfer, as demonstrated by wireless charging technologies that use fields rather than electrons.

How does light travel in a circuit?
Light does not carry energy in a circuit.
What is the role of electrons in a circuit?
Electrons are guided by the electric field in a circuit.
How are charges pushed through a circuit?
Electric field created by charges pushes charges through.
What is the significance of the Poynting vector in circuits?
Poynting vector indicates energy flow direction in circuits.
How do transmission lines influence power delivery?
Transmission lines' impedance affects power delivery.

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A video was made about a circuit with light-second long wires connecting to a light bulb one meter away from the battery and switch.
The claim was made that light from the bulb would be visible in 1/c seconds after closing the switch.
The assertion was refuted, stating that communication faster than the speed of light would violate causality.
The explanation provided in the video was deemed misleading and caused confusion.
A scaled-down model of the circuit was created to demonstrate the time delay between applying a pulse and getting a voltage across the resistor.
The misconception that electrons carry energy from the battery to the bulb was clarified.
The electric field, not electrons, pushes charges through the circuit, created by charges on the battery and wires' surfaces.
The electric field is established instantaneously and maintained by the battery, guiding electrons through the circuit.
The surface charge distribution in the wires creates a net electric field, accelerating electrons through the circuit.
The simulation of the circuit using Ansys software showed the electric field radiating out when the switch is closed, generating current in the wires.

13:47

Initially, connected and disconnected wires behave the same, as demonstrated by the Poynting vector simulation.
The Poynting vector indicates the direction of energy flow in a circuit, pointing out of the battery across the gap to the other wire.
Wires are not essential for energy transfer, as demonstrated by wireless charging technologies using fields instead of electrons.
Wires are more efficient in channeling energy from source to load by directing fields.
The lumped element model simplifies complex physics interactions in circuits into discrete circuit elements like resistors.
To account for field interactions between wires, capacitors and inductors are added to the circuit diagram.
The distributed element model for a transmission line includes resistors, capacitors, and inductors for superconducting wires.
The characteristic impedance of transmission lines is calculated using inductance and capacitance values, influencing the power delivered to the load.