Electrical Conductivity of Different Materials | Electrical4U

Summary

This script delves into the concept of electrical conductivity, explaining how it varies among materials like copper and aluminum under the same voltage. It highlights that conductivity, measured in Siemens per meter, is the reciprocal of resistivity and quantifies a material's ability to conduct electricity. The script also introduces conductance, the reciprocal of resistance, with its unit being Siemens, illustrating fundamental electrical properties and their interrelationships.

Takeaways

• 🔌 Conductivity is a measure of a material's ability to allow current to flow when a voltage is applied across it.
• 🔧 Different materials have different current-carrying capabilities, which affects the amount of current that flows for the same applied voltage.
• 📏 The conductivity of a material is inversely related to the resistivity of the material; a higher conductivity means lower resistivity.
• 🛠️ Conductivity is measured in Siemens per meter (S/m), a unit that quantifies the ease with which current can flow through a material.
• 🔄 The property of resistivity is the opposite of conductivity; resistivity measures how much a material opposes the flow of current.
• 📐 The resistivity of a material is denoted by the Greek letter 'ρ' (rho), while conductivity is denoted by the Greek letter 'Λ' (Lambda).
• ♻️ Mathematically, conductivity is the reciprocal of resistivity, expressed as Λ = 1/ρ.
• 🔊 Conductance is the reciprocal of resistance, which is denoted by the letter 'G' and measured in Siemens (S).
• 🔄 The unit of conductance was historically called a 'mho', but it is now standardized as 'Siemens', with 1 Siemens equal to 1 mho.
• 📚 The script explains the fundamental concepts of conductivity, resistivity, and conductance in the context of electrical conduction through materials.
• 📈 Understanding conductivity is crucial for selecting appropriate materials for electrical applications based on their current-carrying capabilities.

Q & A

What is conductivity of a material?

Conductivity of a material is defined as the inducement offered by the conductor to the flow of current and is measured in Siemens per meter.

How does applying the same voltage across different conductors affect the current flow?

Applying the same voltage across different conductors results in different currents flowing through them due to the varying current carrying capabilities of the materials.

Why does a copper conductor carry more current than an aluminum conductor of the same dimensions?

A copper conductor carries more current than an aluminum conductor of the same dimensions because copper has a higher current carrying capability.

What can be concluded from the observation that different materials conduct different amounts of current under the same voltage?

It can be concluded that the current carrying capabilities of different materials are different, which is measured in terms of conductivity.

How is conductivity related to resistivity?

Conductivity is the reciprocal of resistivity. While resistivity measures how a material resists the flow of current, conductivity measures how a material conducts the current.

What symbols are used to denote resistivity and conductivity?

Resistivity is denoted by the Greek letter rho (ρ), and conductivity is denoted by the Greek letter lambda (λ).

How is conductance of a conductor defined?

Conductance of a conductor is defined as the reciprocal of resistance (1/R) and is denoted by the letter G.

What is the unit of conductance in modern engineering?

The unit of conductance in modern engineering is the Siemens (S), although it was previously denoted as Mho.

What does the term 'Mho' refer to?

'Mho' is an older term for the unit of conductance, which is now denoted as Siemens. One Siemens is equal to one Mho.

What is the mathematical relationship between conductivity and resistivity?

The mathematical relationship between conductivity (λ) and resistivity (ρ) is that conductivity is the reciprocal of resistivity, expressed as λ = 1/ρ.

Outlines

00:00

🔌 Understanding Material Conductivity

This paragraph introduces the concept of conductivity in materials. It explains how the flow of current varies across different conductors when subjected to the same voltage, using the example of aluminium and copper conductors with identical dimensions. The paragraph clarifies that conductivity measures a material's ability to conduct electricity and is the reciprocal of resistivity, with the unit of measurement being Siemens per meter (S/m). The relationship between resistivity (denoted by the Greek letter 'rho') and conductivity (denoted by Lambda) is established, where Lambda equals 1/rho.

Keywords

💡Conductivity

Conductivity is the ability of a material to allow the flow of electric current through it. It is defined as the inducement offered by the conductor to the flow of current and is measured in siemens per meter. In the script, it is explained how different materials like copper and aluminum exhibit different levels of conductivity, with copper having higher conductivity than aluminum for the same applied voltage.

💡Voltage

Voltage is the electrical potential difference between two points in a circuit. It is the driving force that pushes the current through a conductor. The script discusses how applying the same voltage across conductors of the same dimension but different materials results in varying currents due to differences in conductivity.

💡Current

Current is the flow of electric charge through a conductor. It is measured in amperes. The script illustrates that for the same voltage, the current flowing through different materials (like copper and aluminum) will differ, highlighting the concept of conductivity.

💡Resistivity

Resistivity is the property of a material that opposes the flow of electric current. It is the reciprocal of conductivity and is denoted by the symbol 'ρ' (rho). The script explains that resistivity measures how much a material resists current flow, and thus, materials with low resistivity have high conductivity.

💡Copper

Copper is a metallic element known for its high electrical conductivity. The script uses copper as an example to show that it allows more current to flow compared to aluminum when the same voltage is applied, demonstrating its superior conductivity.

💡Aluminum

Aluminum is a metallic element that, while conductive, has a lower conductivity than copper. The script compares aluminum to copper, noting that for the same voltage, aluminum conducts less current, which highlights its lower conductivity.

💡Dimensions

Dimensions refer to the length and cross-sectional area of the conductors used in the examples. The script specifies that conductors of the same dimensions but different materials (copper and aluminum) are compared to illustrate the difference in conductivity.

💡Conductance

Conductance is the reciprocal of resistance and measures how easily a conductor allows the flow of electric current. It is denoted by 'G' and measured in siemens. The script transitions from discussing conductivity to conductance, explaining that conductance is another way to quantify a material's ability to conduct electricity.

💡Resistance

Resistance is the opposition to the flow of electric current through a conductor. It is measured in ohms. The script explains that conductance is the reciprocal of resistance, and a lower resistance implies higher conductance and vice versa.

💡Siemens

Siemens is the unit of measurement for conductance. One siemens (S) is equal to the conductance of a conductor with a resistance of one ohm. The script uses siemens to explain how conductance is quantified in modern engineering, emphasizing the relationship between resistance and conductance.

Highlights

Conductivity of a material is defined as the inducement offered by the conductor to the flow of current.

When voltage is applied across a conductor, the current flowing through it varies depending on the material of the conductor.

For the same applied voltage, current in a copper conductor is higher than in an aluminum conductor of the same dimensions.

Different materials with the same dimensions will carry different currents for the same applied voltage.

Current carrying capability of materials is measured in terms of their conductivity.

Conductivity is measured in Siemens per meter.

Conductivity is the opposite property of resistivity.

Resistivity measures how a material resists the flow of current.

Mathematically, conductivity is the reciprocal of resistivity.

Resistivity of a material is denoted as rho (ρ).

Conductivity of a material is denoted as lambda (λ) and it equals 1 divided by rho (ρ).

Conductance of a conductor is the reciprocal of resistance.

Conductance is denoted by the English letter G.

The unit of conductance is Siemen (S), formerly known as mho.

One Siemen is equal to one mho.

Transcripts

let us try to Define what conductivity

of a material

is whenever we apply voltage across a

conductor there will be current flowing

through that but for the same voltage

this current will not be same for all

conductors of same

Dimension that that means if you use an

aluminium conductor and measure the

current through it and then you use a

copper conductor of same Dimension that

is of same length and cross-section and

measure the current through it you will

find the current in Copper conductor is

more than that of aluminium conductor

for same applied

voltage this is because current carrying

capability of copper is more than that

of

aluminium again if we do the same

observation by using same dimensional

conductors of different materials we

will find different currents flowing

through them for same applied

voltage from these observations we can

conclude that current carrying

capability of different materials are

different this current carrying

capability of a particular material is

measured in terms of conductivity of

that

material and conductivity is defined as

the inducement offered by the conductor

to the flow of current and is measured

in Sims per

meter by this explanation it is quite

clear that conductivity of material is

opposite property of

resistivity we we know that by

resistivity we measure how a material

resist the flow of current through

it hence mathematically conductivity is

the reciprocal of

resistivity resistivity of a material is

denoted as row and conductivity of the

material is generally denoted as Lambda

and it is equal to 1 by

row this was all about conductivity of a

material now we will try to understand

what is conductance of a

conductor the reciprocal of resistance

that is 1 by R is called conductance and

is denoted by English letter

G the unit of conductance is

Mo now in modern engineering the unit is

denoted as Simons although Mo and

Simmons are same that is one Simmons

equal to one

Mo thank you