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How to Reduce the Impedance of Copper

As electrons flow through metallic wires they scatter off one another and off wire boundaries. This leads to a macroscopic phenomena known as resistance, which is a quantity used by electricians, engineers and scientists. When alternating currents (AC) flow through wires, they also scatter, but now the scattering depends upon a number of other factors including the frequency of the AC flow. This phenomena is called impedance. Both the resistance and impedance of a copper wire can be decreased by making any one of the three simple changes to the wire geometry, listed below.

Things You'll Need

Copper wire of various widths, thicknesses and lengths

Instructions

- 1
  Make the wire length as short as possible. Resistance and impedance take the following form: R=Rho*L/t*w. Rho is the resistivity of the material: this is intrinsic to the type of material so cannot be changed for the case of copper. L is the length of the wire. Reducing the value of L reduces the resistance and hence the impedance. t is the thickness of the wire, and w is the width of the wire.
- 2
  Increase the thickness of the wire. Thicker wires have more space for electrons to flow and hence they are less likely to scatter off one another. It also means fewer electrons are nearer the surface so surface scattering plays a smaller role.
- 3
  Increase the width of the wire. Increasing the lateral dimension (width) of the wire means electrons are less likely to scatter off one another.

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