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Why does the skin effect in radio frequency caused?
Skin effect is the tendency of an alternating electric current (AC) to distribute itself within a conductor so that the current density near the surface of the conductor is greater than that at its core. That is, the electric current tends to flow at the "skin" of the conductor, at an average depth called the skin depth. The skin effect causes the effective resistance of the conductor to increase with the frequency of the current because much of the conductor does little. Skin effect is due to eddy currents set up by the AC current. At 60 Hz in copper, skin depth is about a centimetre. At high frequencies skin depth is much smaller.
Steady flow of electrons?
elelctric current
Is Nikola Tesla the inventor of the light bulb?
Nikola Tesla was the inventor of ac/dc current flow along with machines using electricity. He was a electric genius.
What slows the movement of electrons?
Insulators
What happens when a compass is palced near a current carrying conductor?
If the conductor is carrying AC, no effect. If the conductor is carrying DC, then the compass needle will be deflected. Provided the two are close enough, and the DC current is strong enough.
Does electric current flow only on the surface of the copper conductor?
The AC current tend to flow on the surface of the conductor. The higher the frequency, the thinner the skin. This is known as the skin effect. So DC current flow throught the entire conductor but when the signal varies (AC) there is the formation of eddy current in the conductor itself and that pushes the electrons at the surface of the conductor. You can get more information on the skin effect and skin depth on wikipedia : http://en.wikipedia.org/wiki/Skin_effect http://en.wikipedia.org/wiki/Skin_depth
What does not limit current flow in a circuit - capacitance - high conductor resistance or longer conductor?
Of the three choices, capacitance does not limit current flow in an AC circuit.
Does electricity flow on the surface of a wire or through the inside?
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.
How is resistance effected by frequency?
Resistance isn't directly affected by frequency -rather, it depends upon the cross-sectional area, length, and resistivity of a conductor.Having said that, at higher frequencies, current tends to flow towards the surface of a conductor. This is called skin effect, and acts to reduce the effective cross-sectional area of a conductor -resulting in the resistance of that conductor rising somewhat. The higher the frequency, the greater the skin effect, and the higher the resistance.This higher resistance to the flow of AC current is termed AC resistance, and shouldn't be confused with a circuit's reactance which is something entirely different.Additional answer:The skin depth is that distance below the surface of a conductor where the current density has diminished to 1/e of its value at the surface.
How Magnetism effect resistance?
Magnetism does not affect the resistance of a conductor. The factors affecting resistance are the conductor's length, cross-sectional area, and resistivity. As resistivity is affected by temperature, temperature indirectly affects resistance. However, the changing magnetic field surrounding a conductor carrying an AC current causes the current to flow closer to the surface rather than being distributed throughout the cross-section of the conductor. The greater the frequency, the greater this effect. This has the equivalent effect of reducing the cross-sectional area of the conductor, causing its resistance to rise. This is misleadingly called the 'AC resistance' of the conductor!
Can insulator converted into conductor?
Yes, especially in the realm of AC circuitry. Here any surface can function as a wave guide.
What is the relationship between current and frequency in AC circuit?
Two words: skin effect. Now let's chat. Picture a wire with DC flowing through it. We are going to look at a cross section of the wire without interrupting current flow. Make sense? Picture it. When current flows in a wire in only one direction (DC), it uses all the available metal in the wire. Current flow in the middle of the wire will be about the same per unit of cross sectional area as current flow will be near the outside of the wire. Let's switch our DC for some AC. AC (alternating current) will flow in one direction for a while and then reverse direction to flow the other way for a while. Such is AC. And AC will cause current flow that uses all the available cross sectional area of the wire just as DC does, but only at low frequency. At higher and higher frequencies, current flow in the wire will shift away from the center and be more concentrated near the surface of the conductor. Near the skin of the conductor. AC of higher frequencies will promote current flow by skin effect, and that is the effect of frequency in AC current flow.
Why are AC and DC resistance different?
An AC current tends to flow towards the surface of a conductor due to a phenomenon called the 'skin effect', which acts to reduce the effective cross-sectional area of that conductor.Since resistance is directly-proportional to the cross-sectional area of a conductor, the conductor's resistance to an AC current is, therefore, higher than its resistance to a DC current (which distributes itself across the full cross-sectional area). We call this elevated value of resistance, AC resistance.The skin effect increases with frequency to such an extent that, at radio frequencies, there is little point in using solid conductors and tubes are used instead. At mains' frequencies (50/60 Hz), however, the skin effect is moderate and, so, the value of a conductor's AC resistance is only slightly elevated compared to its true resistance.It's important not to confuse the term 'AC resistance' with 'reactance', which is a function of a conductor's inductance and/or capacitance, and the frequency of the supply.
What is the difference between DC and AC resistance?
AC resistance should NOT be confused with IMPEDANCE or REACTANCE.When AC flows through a conductor, it tends to flow towards the surface of that conductor due to a phenomenon called the 'skin effect'. The skin effect, therefore, acts to reduce the effective cross-sectional area of the conductor. Since resistance is inversely-proportional to cross-sectional area, the result is an elevated value of resistance compared with that to DC current. This is called AC RESISTANCE, and it increases with frequency. At mains frequencies (50/60 Hz), AC resistance is not dramatically higher than DC resistance but the difference becomes significant at high frequencies.Read more in the Related link shown below this answer.
Why does the skin effect in radio frequency caused?
Skin effect is the tendency of an alternating electric current (AC) to distribute itself within a conductor so that the current density near the surface of the conductor is greater than that at its core. That is, the electric current tends to flow at the "skin" of the conductor, at an average depth called the skin depth. The skin effect causes the effective resistance of the conductor to increase with the frequency of the current because much of the conductor does little. Skin effect is due to eddy currents set up by the AC current. At 60 Hz in copper, skin depth is about a centimetre. At high frequencies skin depth is much smaller.
Electric flow has sound?
DC doesn't. AC might, since as the voltage varies the conductor experiences a cycle of heating and cooling that can make it vibrate, producing sound.
How can you store ac currrent?
You cannot 'store' current, because, by definition, current is a movement of electrical charge along a conductor. You cannot store something that is moving.
