Sunday, May 26, 2024

# What Is The Definition Of Conductor In Physics

## What Is An Electromotive Force

What are Conductors and Insulators? | Don’t Memorise

The motion of free electrons is normally haphazard. If a force acts on electrons to make them move in a particular direction, then up to some extent random motion of the electrons will be eliminated. An overall movement in one direction is achieved. The force that acts on the electrons to make them move in a certain direction is known as electromotive force, and its quantity is known as voltage and is measured in volts.

## Differences Between Conductor And Insulators

Some key conductor and insulator differences are given in the table below.

 Conductor Materials that permit electricity or heat to pass through it Materials that do not permit heat and electricity to pass through it A few examples of a conductor are silver, aluminum, and iron A few examples of an insulator are paper, wood, and rubber Electrons move freely within the conductor Electrons do not move freely within the insulator The electric field exists on the surface but remains zero on the inside The electric field doesnt exist

## Other Factors That Influence Conductivity

The shape and size of a material affect its conductivity. For example, a thick piece of matter will conduct better than a thin piece of the same size and length. If you have two pieces of a material of the same thickness but one is shorter than the other, the shorter one will conduct better because the shorter piece has less resistance, in much the same way that it’s easier to force water through a short pipe than a long one.

Temperature also affects conductivity. As temperature increases, atoms and their electrons gain energy. Some insulators like glass are poor conductors when cool but good conductors when hot most metals are better conductors when cool and less efficient conductors when hot. Some good conductors become superconductors at extremely low temperatures.

Sometimes conduction itself changes the temperature of a material. Electrons flow through conductors without damaging the atoms or causing wear. Moving electrons do experience resistance, though. Because of this, the flow of electrical currents can heat conductive materials.

Also Check: How Do Noise Canceling Headphones Work Physics

## What Is A Conductor

A conductor, or electrical conductor, is a substance or material that allows electricity to flow through it. In a conductor, electrical charge carriers, usually electrons or ions, move easily from atom to atom when voltage is applied. Most metals like copper are considered good conductors, while nonmetals are considered bad conductors — that is, insulators.

## From The Gnu Version Of The Collaborative International Dictionary Of English

• noun One who, or that which, conducts a leader a commander a guide a manager a director.
• nounUnited States One in charge of a public conveyance, as of a railroad train or a street car.
• noun The leader or director of an orchestra or chorus.
• noun A substance or body capable of being a medium for the transmission of certain forces, esp. heat or electricity specifically, a lightning rod.
• noun A grooved sound or staff used for directing instruments, as lithontriptic forceps, etc. a director.
• noun Same as Leader .
• noun the largest conductor of an electrical machine, serving to collect, accumulate, or retain the electricity.

You May Like: What Is The Biological Importance Of Photosynthesis For The Ecosystem

## Superconductor Definition Types And Uses

• M.S., Mathematics Education, Indiana University
• B.A., Physics, Wabash College

A superconductor is an element or metallic alloy which, when cooled below a certain threshold temperature, the material dramatically loses all electrical resistance. In principle, superconductors can allow electrical current to flow without any energy loss . This type of current is called a supercurrent.

The threshold temperature below which a material transitions into a superconductor state is designated as Tc, which stands for critical temperature. Not all materials turn into superconductors, and the materials that do each have their own value of Tc.

## A How Does The Type Of Material Affect Resistance Experiment

Hypothesis: For a fixed length and thickness of a conducting wire used, its resistance is affected by the type of material.Variables: Manipulated variable: Types of material of the wire Responding variable: Resistance, R Fixed variable: Thickness, length and temperature of wireOperational Definition: The resistance, R of a conducting wire is given by the ratio of the reading of the voltmeter to the reading of the ammeter.Method:

• The electrical circuit as shown in Figure is set up.
• Wire P is connected across terminals X and Y.
• The switch is closed and the rheostat is adjusted to fix the ammeter reading for the current, I = 0.5 A. The reading of the voltmeter for potential difference, V is recorded in a table.
• The value of the resistance, R = V/I is calculated.
• Steps 2 to 4 are repeated by replacing wire P with: Wire Q: 50 cm constantan wire with s.w.g. 24 Wire 5: 50 cm copper wire with s.w.g. 24
• Results:

• The resistance, R of the eureka wire is the highest whereas the resistance, R of the copper wire is the lowest.
• The measure of a materials ability to oppose current flow is also known as the resistivity, p of the material. Thus we can conclude that for a fixed length and thickness of a wire, the resistance varies with the type of material used in the wire.
• Don’t Miss: Hmh Geometry Teacher Edition With Solutions

## Factors Affecting Resistance Of A Wire Experiment

Aim: To investigate the factors affecting resistance.Problem: What are the factors affecting the resistance of a conducting wire?Materials: 50 cm eureka wire , 50 cm constantan wire , 50 cm copper wire , 100 cm constantan wire Apparatus: Ammeter , voltmeter , battery holder, rheostat , switch, connecting wires, three 1.5 V dry cells

## Conventional Current Flow Vs Electron Flow

Conductors and Insulators | Physics | Khan Academy

There is a lot of confusion around conventional current flow and electron flow. In this section, let us understand their differences.

Conventional Current Flow vs Electron Flow

#### Conventional Current Flow

The conventional current flow is from the positive to the negative terminal and indicates the direction in which positive charges would flow.

#### Electron Flow

The electron flow is from negative to positive terminal. Electrons are negatively charged and are therefore attracted to the positive terminal as unlike charges attract.

Recommended Reading: Is Psychology Bsc Or Ba

## Things That Don’t Conduct Electricity And Things That Do

• Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
• B.A., Physics and Mathematics, Hastings College

What makes a material a conductor or an insulator? Simply put, electrical conductors are materials that conduct electricity and insulators are materials that do not. Whether a substance conducts electricity is determined by how easily electrons move through it.

Electrical conductivity is dependent on electron movement because protons and neutrons don’t movethey are bound to other protons and neutrons in atomic nuclei.

## Application Of Electrical Conductors

Some of the applications of electrical conductors are mentioned below as follows:

• Mercury is a popular component of thermometers to measure the bodys temperature.
• Aluminum is used in the production of foils for storing food items. Aluminium is also utilized for the making of fry pans that keep heat in a hurry.
• Iron is a material commonly utilized in the manufacturing of motor vehicles to transfer heat.
• The iron plate is composed of steel that absorbs heat quickly.
• Conductors are used in radiators in cars to remove the heat of the motor.

Enjoy learning Physics concepts like this and many more with the Testbook app. This app is created by experts to help students excel in every type of competitive exam. Download the Testbook app and start your learning journey for your competitive exam.

Don’t Miss: Glencoe Algebra 1 3 4 Practice Direct Variation

## Based On Composition Of Material

Before making the final composition of conductors, there are various important factors that are strictly taken into consideration such as flexibility, tensile strength, mechanical strength, production cost, etc.

Therefore, depending on the need of the environment, the composition of electrical conductors is chosen accordingly.

• Phosphor Bronze Conductors
• Cadmium Copper Conductors, etc.

## The Characteristics Of An Electrical Conductor

An ideal conductor exhibits the following characteristics when it is in equilibrium:

A conductor is a device that allows the movement of electrons and ions in a system.

The electrical field of a conductor is zero, allowing electrons to move freely through it.

The charge density of a conductor is equal to zero.

There are no free charges anywhere else on the conductor except on its surface.

The potential difference between the conductors ends is the same.

A wide variety of metals are excellent conductors of electricity. Insulators are defined as a plastic layer that protects an electrical conductor from contact with the surrounding environment. This keeps us from receiving an electric shock.

Recommended Reading: Geometry Nation Section 1 Test Yourself Answers

## Based On Ohmic Response Of Material

Based on the fact that whether a conductor is following Ohms Law or not, conductors can be bifurcated into two types:-

#### Ohmic Conductors

According to the definition of conductors, conductors that follows Ohms law are Ohmic Conductors. Examples of Ohmic conductors are Copper, Aluminium, etc.

#### Non-Ohmic Conductors

Conductors that do not follow ohms law are Non-Ohmic conductors. Examples of non-ohmic conductors are Zener diode, a filament of the bulb, etc.

## Temperature’s Effects On Conductivity

Temperature and conductivity are inversely related, meaning rising temperatures have an adverse effect on conduction. As temperatures increase, the vibration in conductor molecules also increases. This hampers the smooth flow of electrons, thereby decreasing the material’s conductivity.

Further, rising temperatures lead to the breaking of bonds in the conductor molecules, thereby releasing electrons. This leaves the material with fewer electrons, thereby reducing the material’s ability to conduct an electrical current through it.

You May Like: What Does I Stand For In Physics

## From The American Heritage Dictionary Of The English Language 5th Edition

• noun One who conducts, especially.
• noun One who is in charge of a railroad train, bus, or streetcar.
• nounMusic One who directs an orchestra or other such group.
• nounPhysics A substance or medium that conducts heat, light, sound, or especially an electric charge.
• noun A lightning rod, as on a house or barn.

## Dieletrics And Their Breakdown

Resistance of a Conductor | Electricity and Circuits | Don’t Memorise
• Dielectric breakdown is the phenomenon in which a dielectric loses its ability to insulate, and instead becomes a conductor.
• Dielectric breakdown is the phenomenon in which a dielectric loses its ability to insulate, and instead becomes a conductor.
• Dielectrics are commonly used either to isolate conductors from a variable external environment or to isolate conductors from one another .
• Under certain conditions, however, a material that is an insulator can become a conductor.
• This point is known as the breakdown voltage.
• In the case where a conductor loop is moving into magnet shown in , magnetic force on a moving charge in the loop is given by \$evB\$ .
• “…… for example, the reciprocal electrodynamic action of a magnet and a conductor.
• The observable phenomenon here depends only on the relative motion of the conductor and the magnet, whereas the customary view draws a sharp distinction between the two cases in which either the one or the other of these bodies is in motion.
• For if the magnet is in motion and the conductor at rest, there arises in the neighbourhood of the magnet an electric field with a certain definite energy, producing a current at the places where parts of the conductor are situated.
• But if the magnet is stationary and the conductor in motion, no electric field arises in the neighbourhood of the magnet.
• Recommended Reading: What Is Microevolution In Biology

## What Are The Factors That Affect The Resistance Of A Conductor

• In the telecommunications and power industries, it is essential to select suitable electric cables to carry electric currents for many different purposes.
• The most important factor to be considered when selecting the cables is the resistance of the conductors in the cable.
• The resistance of a conductor is affected by the type of material it is made of and by its length, thickness and temperature.

Factors on which resistance of conductor depends

• Effect of the length on the resistance of a conductor The resistance of a conductor is directly proportional to the length. That is Resistance of a conductor Length of the conductor.
• Effect of the area of cross-section on the resistance of a conductor The resistance of a conductor is inversely proportional to its area of cross-section. That is, Resistance of a conductor \ If the area of cross-section of the conductor is doubled, its resistance gets halved.
• Effect of temperature on the resistance of a conductor The resistance of all pure metals increases with a rise in temperature. The resistance of alloys increases very slightly with a rise in temperature. For metal when temperature increases resistance increases and for semiconductors when temperature increases resistance decreases.
• Thus the resistance, R of a given conductor:

• Is directly proportional to its length, l
• Is inversely proportional to its cross-sectional area, A
• Depends on the type of material or the resistivity,
• Is affected by temperature

## What Is The Definition Of Resistance In Physics

What is Resistance of a Conductor The movement of electron gives rise to the flow of current through metals. The moving electrons collide with each other as well as with the positive ions present in the metallic conductor. These collisions tend to slow down the speed of the electrons and hence oppose the flow of electric current. The property of a conductor by virtue of which it opposes the flow of electric current through it is called its resistance.

• The measure of a conductors opposition to current flow is known as the resistance of the conductor. Different conductors have different resistance to current flow.
• Resistance is denoted by the letter R.
• The resistance, R of a conductor is defined as the ratio of potential difference, V across the conductor to the current, I flowing through it. Thus:
• The SI unit of resistance is ohm. The ohm is denoted by the Greek letter called omega.
• Resistance is a scalar quantity.
• One ohm is the resistance of a conductor when a potential difference of 1 volt applied across its ends causes a current of 1 ampere to flow through it.

Also Check: What Is Internal Transport In Biology

## Discovery Of The Superconductor

Superconductivity was first discovered in 1911 when mercury was cooled to approximately 4 degrees Kelvin by Dutch physicist Heike Kamerlingh Onnes, which earned him the 1913 Nobel Prize in physics. In the years since, this field has greatly expanded and many other forms of superconductors have been discovered, including Type 2 superconductors in the 1930s.

The basic theory of superconductivity, BCS Theory, earned the scientistsJohn Bardeen, Leon Cooper, and John Schriefferthe 1972 Nobel Prize in physics. A portion of the 1973 Nobel Prize in physics went to Brian Josephson, also for work with superconductivity.

In January 1986, Karl Muller and Johannes Bednorz made a discovery that revolutionized how scientists thought of superconductors. Prior to this point, the understanding was that superconductivity manifested only when cooled to near absolute zero, but using an oxide of barium, lanthanum, and copper, they found that it became a superconductor at approximately 40 degrees Kelvin. This initiated a race to discover materials that functioned as superconductors at much higher temperatures.

In the decades since, the highest temperatures that had been reached were about 133 degrees Kelvin . In August 2015, a paper published in the journal Nature reported the discovery of superconductivity at a temperature of 203 degrees Kelvin when under high pressure.

## What Is The Conduction Process Of Heat Transfer

Ans : Conductor of electricity. The conductor is a metal that permits electrical current to flow through it. Metals such as copper, aluminium, and their alloys are commonly used as electrical conductors.

Ans : Electric power is transported from generating plants to clients via overhead conductors. A conductor is an object or type of material in physics and electrical engineering that permits charge to travel in one or more directions. Metals are commonly used as electrical conductors.

Ans : Metals such as copper, aluminium, and their alloys are commonly used as electrical conductors. When a potential difference is introduced across the atoms in an electrical conductor, the electrical charges transfer from one to the other. In the form of wire, electrical conductors are utilised.

Ans: Give an example of the Fourier law of conduction. The area measured normal to the direction of heat flow and the temperature gradient in that direction determine the rate of heat conduction.

Ans: This article explains how heat is transferred by conduction. The transfer of heat by colliding particles is known as conduction. Solids are superior conductors than liquids and gases because the particles are so close together.

Read Also: How To Treat Psychological Trauma

## C How Does The Cross Sectional Area Affect Resistance Experiment

Hypothesis: For a fixed length of a conducting wire, the thicker the wire, the smaller the resistance.Variables: Manipulated variable: Thickness of wire Responding variable: Resistance, R Fixed variable: Type, length and temperature of wireOperational Definition: The thickness of a conductor is determined by the value of its s.w.g. The resistance, R of a conducting wire is given by the ratio of the reading of the voltmeter to the reading of the ammeter.Method:

• The same electrical circuit as shown in above Figure is used.
• Wire Q is connected across terminals X and Y.
• The switch is closed and the rheostat is adjusted to fix the ammeter reading for the current, I = 0.5 A. The reading of the voltmeter for potential difference, V is recorded in a table.
• The value of the resistance, R = V/I is calculated.
• Steps 2 to 4 are repeated by using 50 cm constantan wires with s.w.g. 30 and s.w.g. 34.
• Results:

Discussion:

• The value of s.w.g. of a wire corresponds to its diameter. A wire with a larger s.w.g. has a smaller diameter.
• The cross-sectional area, A of a wire can be determined from its diameter, D by the equation:
• The resistance, R of a wire is inversely proportional to its cross-sectional area, A. The thicker the wire, the lower the resistance. The hypothesis is accepted. .