Electrical Conductors and Insulators Quiz

Electrical Conductors and Insulators

• Insulators like plastic and rubber confine electrical charges, preventing the flow of electrons and protecting people from electric current exposure.
• Examples of conductors include copper, gold, and saltwater, while insulators include plastic, rubber, and pure water.
• Conductors and insulators are used to control the flow of electricity and have real-world applications like oven mitts for insulation and baking pans for conduction.
• Electrical resistance is the capacity of a conductor to resist the flow of electrical current and is measured in ohms in the SI system.
• Conductance is the opposite of resistance and is measured in siemens, denoting the degree to which electric current can flow through a conductor.
• Electrical resistance in conductors is caused by the random motion and collisions of free electrons with the atoms of the conductor.
• Ohm's law states that the voltage across a conductor is directly proportional to the electric current flowing through it, with the proportionality constant being resistance.
• The electrical resistance of a conductor is affected by its length and cross-sectional area, as well as its resistivity, which is an inherent property of the conductor.
• The resistivity of a conductor is independent of its dimensions and is measured in ohm-metre.
• The resistance and resistivity of a conductor are both directly proportional to its temperature, causing an increase in resistance with higher temperatures.
• Different types of electrical resistance depend on the type of current flowing through a material.
• The temperature coefficient of resistivity varies with the material of the conductor and affects the resistivity at different temperatures.