Does electricity flow on the surface of a wire or through the inside?

Answer 1

With direct current, the charge flow is distributed throughout the cross-sectional area of a conductor. With alternating current, the charge flow tends to flow towards the surface of a conductor due to what is called the 'skin effect'. The higher the frequency, the greater the skin effect.

In fact, at microwave frequencies, pipes are used because no current would flow through the center of the conductor - these pipes are known as 'waveguides' the signal flows through the hollow center of the pipe as electromagnetic radiation and the pipe is used as a grounded shield only to prevent the escape.of this electromagnetic radiation.

Answer 2

At DC and very low frequency AC, current flows inside the bulk of a conductor. As frequency increases, the skin effectgradually kicks in and AC current flow gets more restricted to the outside surface. At RF the AC current is completely limited to the outside surface. At microwaves the effect is so strong that we leave the inside out entirely and only provide the outside, this is called a waveguide: microwave currents flow on the outside and microwave electromagnetic fields fill the hollow insides (if the inside was not hollow these fields could not propagate and there would be high signal losses).

Answer 3

flow through
'Voltage' is simply another name for potential difference, which is the difference in potential between two different points -so, clearly, a voltage is impressed across a circuit. Current, which is a slow drift of electrical charge through a circuit.

Answer 4

Electrical current flows along the surface of a metal, so no, it does not flow through the core of a wire, just the surface.