The resistance of a conductor depends on the cross sectional area of the conductor, the length of the conductor, and its resistivity. It is important to note that electrical conductivity and resistivity are inversely proportional, meaning that the more conductive something is the less resistive it is. The best insulator in the world right now is most probably aerogel, with silica aerogels having thermal conductivities of less than 0. The resistance does not depend on the weight of the wire.
Therefore, the correct option is weight. The longer a wire is the more resistance it has due to the longer path the electrons have to flow along to get from one end to the other. The larger the cross sectional area, the lower the resistance since the electrons have a larger area to flow through. This will continue to apply no matter how thick the wire is.
Increased temperature results in reduced resistance in insulators and partial conductors, such as carbon. Resistance is defined as the opposition to the flow of electrical current through a conductor. The best conductors in the world, excluding superconductors, have some resistance.
An insulator is a material whose internal electric charges do not flow freely. Conductors A material through which heat can move easily is called a conductor. Iron, silver, aluminum, stainless steel, and copper are all examples of metals that are good conductors. Good example of insulators are ceramic rope, fiberglass, mineral wool. OHM stands for resistance. The more resistance it has, the higher its rating.
As the length increases, the number of collisions by the moving free electrons with the fixed positive ions increases as more number of fixed positive ions are present in an increased length of the conductor. As a result, resistance increases. An electric current flows when electrons move through a conductor, such as a metal wire.
The moving electrons can collide with the ions in the metal. This makes it more difficult for the current to flow, and causes resistance. Answer: the current in a given circuit is inversely proportional to the resistance in the circuit, which means that the current will decrease if the resistance is increased.
Materials that have low resistance to electric current are called electric conductors. Many metals are good electric conductors. Materials that have high resistance to electric current are called electric insulators. Materials that do not allow electricity to pass easily through them are called insulators.
Does an insulator have high resistance? Why do conductors have a low resistance? The larger conductor will have a lower resistance due to the increased volume of conductive material. Why are insulators bad conductors of heat? Materials that are poor thermal conductors are called thermal insulators. Do conductors have low resistance?
If the voltage is high enough, electric current can be made to flow through even materials that are generally not considered to be good conductors. The unit of resistance is the ohm. At the other extreme, electrical insulators have resistivities in the range to ohm-metres. Increased temperature increases the resistance of conductors, but does not affect insulators. Resistance increases, in case of conductor, with increase in temperature and decreases, in case of insulator, due to increase in temperature.
So, there are excess electrons in the conduction band of a conductor. Materials that are good conductors of thermal energy are called thermal conductors. Gases such as air and materials such as plastic and wood are thermal insulators.
A material that does not easily transmit energy, such as electric current see also current or heat. Materials such as wood, plastic, and ceramics are insulators. Fiberglass is an example of a heat insulator.
A poor conductor means that the substance will not easily conduct heat or electricity or both as easily as a conductor. For example, sand is a poor conductor of heat and electricity. During the daytime, when the sunlight hits the sand, it traps the heat instead of conducting it.
Energy, such as heat, transfers through some materials easily. These materials are called conductors. These materials include plastic, cork, wood, Styrofoam, and rubber.
Thermal insulation is the reduction of heat transfer i. The glass jar can conduct heat relatively well. However, if the air pockets inside the insulating material are separated from each other, heat flow from one air pocket to another cannot happen easily. Non-metals are generally bad conductors or insulators. Metals, on the other hand, are good conductors.
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