0
Materials are classified as being conductors, semiconductors, or insulators according to their resistivity.
Resistivity is defined as being 'the resistance of a unit length of a substance of uniform cross section'. In the SI system this equates to the resistance across opposite faces of a one-metre cube of that substance, and is expressed in ohm metres. Note that a one-'metre cube' is not the same thing as a 'cubic metre'.
So, for
conductors: resistivity range 10-8 - 10-6 ohm metres
semiconductors: resistivity range 10-6 - 107 ohm metres
insulators: resistivity range 107 - 1023 ohm metres
To appreciate the difference between these astronomical figures, consider the following:
A 25-mm length of mica (an insulator) of cross-sectional area 2.5 mm2 cross-sectional area will have a resistance of 100 x 1015 ohms. A copper wire, having the same cross-sectional area and resistance, will have a length of 14.29 x 1018 metres! That works out to: 14 290 000 000 000 000 kilometres long!!!!
What else can I help you with?
Why do you use semiconductor why not conductors and insulators by changing their properties?
We use semiconductors instead of conductors and insulators by changing their properties because the properties of a semiconductor lies between that of a good insulator ant that of a good conductor. Any of the materials obtained depends on the level of doping.
What is the difference between conduct and insulate?
Insulation is keeping the heat inside, trapping it and not letting out. Conduction is letting a flow, such as electricity, pass through the material. for example, metal is a wonderful conductor of heat and electricity, but a bad insulator. However, wool is a good insulator and a bad conductor. :) hope that helps!
Gfci circuitry checks for differences in current between the?
...hot and neutral conductors. (Sounds a lot like a homework question. If so, spend a little more time reading the textbook!)
Does capacitance exists between two current carrying conductors?
Capacitance exists between any two conductors, current carrying or not.
What do you call the material that covers a conductor?
Most wire conductors are covered with an insulator. This material is intended to prevent accidental connection between multiple conductors or between conductors and other objects that may conduct electrical or electronic signals (including humans).
Substance in between conductors and insulators used in transistors?
Semiconductors
How are materials classified on the basis of resistivity?
Materials can be classified based on their resistivity as conductors, semiconductors, or insulators. Conductors have low resistivity, allowing electric current to flow easily. Semiconductors have resistivity in between conductors and insulators, and their conductivity can be controlled. Insulators have high resistivity and do not allow electric current to flow easily.
What are Conductors Insulators Semiconductors?
Conductors are materials that allow electricity to flow easily, like metals. Insulators are materials that do not allow electricity to flow, like rubber or glass. Semiconductors are materials that have properties between conductors and insulators, and are commonly used in electronics.
Materials that are not good conductors or and not good insulators are called?
Semiconductors. They have conductivity between conductors and insulators and are used in electronic devices like transistors and diodes.
Do semi conductors permit flow of electricity better than insulators?
Yes, semiconductors allow the flow of electricity better than insulators, but not as well as conductors. Semiconductors have conductivity values between those of conductors and insulators, making them useful for controlling the flow of electric current in electronic devices.
What Materials with electrical characteristics that fall between those of insulators and conductors are considered?
Materials with electrical characteristics that fall between insulators and conductors are known as semiconductors. Semiconductors have an intermediate level of electrical conductivity, making them valuable for use in electronic devices such as transistors and diodes. They can be controlled to act as either insulators or conductors using techniques like doping or applying voltage.
Are scissors conductors?
They are Conductors, not much for insulation though. Differences between conductors and insulators? Conductors let energy such as electricity .
How are substances classified on the basis of resistivity?
Substances are classified based on their resistivity as conductors, insulators, or semiconductors. Conductors have low resistivity and easily allow the flow of electric current. Insulators have high resistivity and inhibit the flow of electric current. Semiconductors have resistivity values between conductors and insulators, making them suitable for controlling the flow of current in electronic devices.
Why semi conductors are insulators at ordinary temperature?
Semiconductors are not insulators at ordinary temperatures; they exhibit intermediate conductivity between conductors and insulators. At low temperatures, semiconductors can behave more like insulators due to reduced thermal energy allowing fewer charge carriers to move within the material. However, as temperature increases, more electrons are excited into the conduction band, increasing conductivity.
What material has resistance between a conductor and a insulator?
Semiconductors have resistance levels between that of conductors and insulators. They conduct electricity better than insulators but not as well as conductors, making them useful in electronic devices. Examples include silicon and germanium.
Why do you use semiconductor why not conductors and insulators by changing their properties?
We use semiconductors instead of conductors and insulators by changing their properties because the properties of a semiconductor lies between that of a good insulator ant that of a good conductor. Any of the materials obtained depends on the level of doping.
What are the classification of materials according to electrical conductivity?
Most substances fall into two categories - conductors and insulators. Conductors are those which electricity can pass through relatively easily. Metals are the usual example, but other substances such as graphite and polar liquids such as water are also good conductors. Insulators are poor conductors: those that electricity cannot pass through easily. Most plastics are insulators. Some substances fall in between: these are semiconductors, which allow electricity through in some instances, but not in others. This property makes them very useful in electronics. Some substances can be such good conductors that, under some circumstances, they can allow electricity to pass through them with no resistance at all. These are called superconductors.
