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# definition of conductors and insulators

Question:Um. In school we are learning science. I was wondering. On tires, when you drive, would rubber be an insulator or a conductor. And what about the metal? If you have any other examples of conductors and insulators feel free to write them, while also answering.

Answers:Anything can be a conductor with high enough voltage. Usually when you talk of insulators or conductors it just means relative to one another which conducts electricity better or worse than the other. I used to be an engineer at Firestone tire and we would run electricity through tire treads simulating a lightning strike and/or static electric build up on the tire surface. Now rubber was an insulator up to about 40000 ohms but after that the electricity traveled right through it. Actually the electricity travels around the surface of it With static charge it was even lower. The electricity would build up on the outside shell of the tire and discharge to any ground. The steel in the wire reinforcement of the tire does conduct electricity but it is completely surrounded by rubber and makes no difference to conduction unless your talking lightning strikes. Pure water does not conduct electricity. You need to add something that breaks into ions that conduct electricity. Sow ater is an insulator until you put salt into it , then it becomes a conductor. Metals are considered conductors because they offer very low resistance to electric flow. Way less than 1 ohm per 100 ft of wire is common. Ohms is a measurement of resistance to electric flow. The higher the ohms, the more the substance goes from being considered a conductor to a insulator. Rubber is considered an insulator because it takes about 40000 ohms to traverse a 1/4" of rubber. Silver is the best conductor. Copper is second best and aluminum the 3rd best.It offers the least resistance to electricity. Air, vinyl, rubber, wood, wool , synthetic fabrics are all considered good insulators

Question:Is air a better insulator or conductor? Why?

Answers:It is a better insulator because it relative low density does not allow for effective transfer of energy. This is why you will preserve body heat better by dressing in several layers as opposed to one thick layer, and why storm windows are multi-paned, with air in between, as opposed to one thick pane.

Question:eh, i kinda suck at science so yeah, complete the following paragraph using the words from the list below. - collide - diffuse - move faster - transfer - vibrate. When a metal bar is heated at one end, the free electrons at that end ______ They ________ and ______ with other free electrons. As a result, they ______ energy from the hot end of the metal. The free electrons ________ with the atoms and make them ______ more. 2. Choose a material from the list below to answer each of the following questions. -Copper -Felt -Plastic -Steel a) which material is the best conductor? b)which material is used to make saucepan handles from? c)which material would be used the best for loft insulation? d)what material is used to make heating radiators from? Final question :) Name three good conductors and three good insulators that you might find at a typical barbecue. Good conductors : Good insulators : please help! :) xxxx

Answers:When a metal bar is heated at one end, the free electrons at that end MOVE FASTER. They DIFFUSE and COLLIDE with other free electrons. As a result, they TRANSFER energy from the hot end of the metal. The free electrons COLLIDE with the atoms and make them _VIBRATE more. a) which material is the best conductor? COPPER b)which material is used to make saucepan handles from? PLASTIC (heat resistant, e.g. bakelite ) c)which material would be used the best for loft insulation?FELT d)what material is used to make heating radiators from? STEEL ( actually cast iron for steam radiators so they have large thermal inertia; hot water radiators use aluminum fins )

Question:Two new materials have been discovered. One is shiny and has a metallic look, while the other is dull and has a non-metallic look. Although you think that one is a conductor and the others an insulator, you want to be certain. Describe a test you could do to test the conductivity of these two materials?