What are properties of conductors?
Soluções para a tarefa
Resposta:
Resistance
Inductance
The electrical filed inside the conductor is zero
The charge density inside the conductor is zero
Free charge exists only on the driver's surface
On the conductor surface, the electric field is normal to the surface
Explicação:
Electrical conductor resistance
Conductors of electricity generally possess very low resistance to the flow of electricity. Ideally, the resistance of a perfect conductor is zero. However, practically the resistivity of conductors varies from low to high. The conductor with low resistivity / high conductivity is used as a conductor for coils of electrical machines, for transmission lines, for electrical contact, ground wire, etc. High resistivity / low conductivity conductive materials are used for manufacturing incandescent lamp filaments and heating elements. Electric heaters, ovens, ovens.
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Electrical conductor inductance
When a conductor is used in the AC supply, a magnetic flux is produced. Which is consists of two parts. Internal flow and external flow. The value of the internal flow is very low compared to the external flow. Due to this flux connection to the conductor itself, an inductance comes into play. This inductance results in additional voltage drop across the conductor. Furthermore, this inductance also affects the current distribution in the cross-sectional area of the conductor. Because of this, current prefers to flow through the outside of the cross-sectional area. This effect is called the skin effect. This distribution of current over the cross-sectional area is also effected by the connection of flux to the conductor due to the current flowing through the nearby conductor. This is called the proximity effect of these skin effects and proximity effects exist only for the supply of alternating current. These effects do not exist for the DC supply, as the flux produced by the DC supply remains constant over time.
Electric Field Inside the Conductor is Zero
The electric field inside a perfect conductor is zero. If the electric field exists inside the conductor, it will extract a force on the electron and accelerate it. But under equilibrium conditions, the net force on the electron is zero. Therefore, the electric field does not exist inside the conductor. It means that the electric field must be external to the conductor. This property of the conductor makes it suitable to be used for electrostatic shielding of electrical equipment.
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Charge density inside the conductor is zero
This electrical charge does not exist inside the conductor. The mutual electrostatic repulsion force between similar charges, ie electrons, requires the electrons to be as far away as possible. This electrostatic repulsion force pushes electrons to the surface in the conductor. Since there is no electrical charge inside the conductor, it results in zero charge density within the conductor.
The free charge exists only on the driver's surface
As discussed above, the charge particle does not exist inside the conductor. Due to the electrostatic repulsion force, electrons move to the outer surface of the conductor. Because no electrical charge exists inside the conductor. Thus, the free electrical charge leaves only on the surface of the conductor.
Conductor surface, the electric field is normal to the surface
If we go through the boundary condition of dielectric to the conductor, the electric field is normal to the conductor's surface and the tangent part of the electric field to the surface is zero. It means that the electric field strength is normal to the conductor surface and the tangential part of the electric field strength is zero.