Which of the following are good conductors due to the ability of the electrons in the atoms to move around freely?
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Next: Electrometers and Electroscopes Up: Electricity Previous: Historical Introduction Suppose that we were to electrically charge two isolated metal spheres: one with a positive charge, and the other with an equal negative charge. We could then perform a number of simple experiments. For instance, we could connect the spheres together using a length of string. In this case, we would find that the charges residing on the two spheres were unaffected. Next, we could connect the spheres using a copper wire. In this case, we would find that there was no charge remaining on either sphere. Further investigation would reveal that charge must have flowed through the wire, from one sphere to the other, such that the positive charge on the first sphere completely canceled the negative charge on the second, leaving zero charge on either sphere. Substances can be classified into two main groups, depending on whether they allow the free flow of electric charge. Conductors allow charge to pass freely through them, whereas insulators do not. Obviously, string is an insulator, and copper is a conductor. As a general rule, substances which are good conductors of heat are also good conductors of electricity. Thus, all metals are conductors, whereas air, (pure) water, plastics, glasses, and ceramics are insulators. Incidentally, the distinction between conductors and insulators was first made by the English scientist Stephen Gray in 1729. Metals are good conductors (both of heat and electricity) because at least one electron per atom is free: i.e., it is not tied to any particular atom, but is, instead, able to move freely throughout the metal. In good insulators, such as glass, all of the electrons are tightly bound to atoms (which are fixed), and so there are no free electrons. Show
Next: Electrometers and Electroscopes Up: Electricity Previous: Historical Introduction Richard Fitzpatrick 2007-07-14 Each material is different and has its characteristics and properties. Some materials have electrically charged particles which are free to move inside them, known as free electrons. When such materials are connected to a battery or a cell, the free electrons start to move and allow electricity to pass through them. The ability of the materials to pass electricity through them is known as conductivity. Depending on the conductivity, materials are classified as conductors, insulators and superconductors. Materials with good mobility of electrons are known as conductors and materials with less mobility of electrons are referred to as insulators. The conductor with the comparatively easy flow of electrons is classified as a good conductor of electricity. In this article, let us know the best conductor of electricity and its properties. What is an Electrical Conductor?If you have to define the meaning of electrical conductors in the simplest way, they are materials that allow electricity to flow through them easily. If we compare two types of material and the first one allows a better flow of electricity through it, then that material is said to be a good conductor of electricity. Some examples of conductors of electricity are
An electrical conductor allows the electric charges to flow through them easily. The property of conductors to “conduct” electricity is called conductivity. Such materials offer less opposition or “resistance” to the flow of charges. Conducting materials allows easy charge transfer because of the free movement of electrons through them.
Most conducting materials used for practical applications are metals. For example, the wire around your house probably uses copper as conducting materials or alloys. The electric plugs have metal in them, and the internal mechanism of your electric irons also uses metals as their conducting material. This is because metals have lots of free electrons and promote mobility. Some of the best metal conductors are Silver (Ag), Copper (Cu) and Gold (Au). The more free electrons present in a metal, the greater its conductivity. Comparatively, silver has better electrical conductivity than copper and gold. Since silver is far more expensive than copper, copper finds its application in all household appliances and circuits. Aluminium is also one of the best conductor of electricity which has a conductivity slightly lesser than copper. It is used in the home’s internal wiring, and most commonly, it is used in combination with copper. Silver oxide batteries are widely used in watches and hearing aids since it is light-weight and durable.
There are some non-metals which are excellent conductors of electricity. For example, carbon in the form of graphite is an excellent conductor of electricity. If you see the structure of graphite, only three of the four carbon atoms are used for bonding. This leaves one electron free for bonding. However, most non-metals are not good conductors of electricity.
Conductors in their solution form are called ionic conductors. For example, saltwater is an ionic solution and is a good conductor of electricity.
Although semiconductors are not as good at conducting electricity as conductors, they still have their uses. Examples of semiconductors are Germanium (Ge) and Silicon (Si). Properties of Electrical ConductorA conductor exhibits the following properties in equilibrium conditions:
Many metals are good conductors of electricity. This is the reason why parts of appliances that need to pass electricity are made of metals. The plastic covering that surrounds an electrical conductor is known as an insulator. It prevents us from getting an electric shock. SuperconductorsThe superconductor is a material that offers no resistance to the flow of electrons and conducts electricity. The superconductivity phenomenon was discovered by Heike Kamerlingh Onnes, the Dutch Physicist in 1911. Superconductors are elements or metallic alloy, when cooled below a certain threshold temperature, lose electrical resistance property and become superconductors. Some of the best superconductors are niobium, cuprate, magnesium and diboride. Frequently Asked Questions – FAQsThe inverse of conductance is called resistance. True. Electric wires are made of metal wires because they are good conductors of electricity. Glass, Plastic and Air are some
common examples of insulators. Among the these, copper is the best conductor of electricity. Is wood a good conductor of electricity or a bad conductor of electricity?Wood is a bad conductor of electricity. Hope you learnt about good conductors of electricity with examples. Stay tuned to BYJU’S and keep falling in love with learning! Watch the video and witness a real-life demonstration of charging by conduction.Which of the following is considered a good conductor?Copper, silver, aluminum, gold, steel, and brass are common conductors of electricity. The most highly conductive metals are silver, copper, and gold.
What is the name for a material with a free electron in its valence ring that allows electricity to flow freely?Materials that have free electrons and allow electrical current to flow easily are called conductors. Many materials do not have any free electrons. Because of this fact, they do not tend to share their electrons very easily and do not make good conductors of electrical currents. These materials are called insulators.
What rocks form when existing rocks are subjected to high temperatures and pressures that cause changes in mineralogy and texture but do not melt?Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineral-rich fluids or, more commonly, some combination of these factors.
How are crystalline rocks formed?Crystalline rocks are formed because of the polymerization of minerals. The Crystalline rocks are called so because of the excess of crystals that are present in them and also because of the highly organized microscopic structures of these crystals for which the highly tensed geological processes are responsible.
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