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• Any movement of charges from one region to another is called current.
• the electric current is defined as the net charge flowing through an area per unit time.
• The SI unit of electric current is ampere (A).
• In plasma, these charges may include both positively- and negatively-charged ions.
• In metals, moving charges or charge carriers are always negative.
• Charges flowing through a surface can be positive, negative, or both.
• The opposite of the conventional current is electron flow.
• The conventional current is defined based on the direction of the flow of positive charges.
• the electric field is zero in a conductor.
• the motion of these electrons is random, there is no net flow of charge in any specific direction; hence there is no current.
• a very slow net motion or drift of the moving charges in the direction of the steady electric force is called the drift velocity
• If q is positive, vd moves in the same direction as E.
• If q is negative, vd moves in the opposite direction to E.
• A diode is a device that allows current to flow in one direction while restricting its flow in the other direction.
• Semiconductors, such as silicon, can be effectively used in this specific application.
• Resistance is the opposition of a material to the flow of charges.
• resistance's SI unit is the ohm (Ω).
• resistance can also be defined as the proportionality factor between the voltage and the current.
• Resistivity is the measure of resistance of a specific material for a given dimension.
• resistivity's SI unit is ohm-meters
• The reciprocal of resistivity is conductivity (σ)
• conductivity quantifies how strongly a material allows charges to flow.
• conductivity's SI unit is siemens per meter
• Semiconductors are materials that have conductivities between the values of conductors and insulators.
• poor electrical conductors, such as plastics and ceramics, are also poor thermal conductors.
• Metals and alloys, being good electrical conductors are also good thermal conductors.
• The human body is considered an electrical conductor, which means that current can easily pass through it.
• Electrocution refers to the injury suffered by a person due to electric shock.
• It can contain about 100 ohms of resistance when immersed in seawater.
• The rate at which electrical energy becomes converted into other forms is referred to as electric power.
• The SI unit for electric power is watt.
• Power rating refers to the maximum power that can “dissipate” from the material without experiencing overheat.
• The total power in both series and parallel connections is equivalent to the power consumed by the individual resistances.