Conductor or conductor of electricity is a material that easily conducts electric current. The nature of its conduction is to move electrons from one electrical point to another easily. The main use of electrical conductors is to carry electric current.
Conductors have atomic nuclei with electrons that are loosely bound and can move freely. The process of conducting electricity occurs when positively charged materials are connected to electrical conductors. The interaction that arises is the transfer of electrons from electrical conductors to positively charged materials.
The easy flow of electric current through electric conductors is due to the fact that the content of electric charges easily moves when an electric field arises, even in very small amounts. The electric field in the conductor is zero as long as it is not electrified.
Conductor and Semiconductor Materials
Definition of Conductor Materials
In everyday life, humans often use objects that use conducting materials to conduct heat and insulating materials to prevent heat from spreading. Conductors and insulators are interrelated properties, so that they can be used simultaneously on an object.
These conductors and insulators have something to do with temperature matter. Temperature is a thing to express the level of heat objects. At the same temperature, the substance with the greater mass will have more heat energy. Heat energy that moves from high temperature to low temperature is called heat. As a form of energy, the SI unit of heat is the joule (J).
The most popular units of heat are the calorie and the kilocalorie. One calorie is the amount of heat energy required to raise the temperature of 1 gram of water by 1 degree Celsius. One calorie is equal to 4.184 J, which is often rounded up to 4.2 J. In addition to the amount of heat and mass of an object that affects the temperature rise is the type of object. The greater the increase in temperature, the greater the heat required. The greater the mass of the object, the greater the heat needed by the temperature.
The heat required to raise the temperature = specific heat × object mass × temperature rise, represented by the following formula:
Q = c × m × Δt.
Q = Heat required
c = specific heat
m = mass of object
Δt = temperature rise
Conductor materials are known as materials that can conduct heat well. Conducting materials have little resistance because their specific resistance is small. Conducting materials have electrons in the outermost shell of atoms whose attraction to the atomic nucleus is weak.
Thus, if the ends of the conductor are connected with only a small voltage, the electrons will move freely, thereby supporting the flow of electrons (electric current) through the conductor. Examples of conductor materials include iron, copper, silver, aluminum, nails, carbon, paper clips, coins.
Definition of Semiconductor Materials
A semiconductor is a material with an electrical conductivity that is in between that of an insulator and a conductor. A semiconductor acts as an insulator at very low temperatures, but at room temperature (high temperatures) it acts as a conductor.
The semiconductor materials that are often used are silicon, germanium, and gallium arsenide. To get objects like this, doping is usually done certain atoms. Germanium was once the only material known to make semiconductor components. But recently, silicon became popular after it was discovered how to extract this material from nature.
Silicon is the second most abundant material on earth after oxygen. Sand, glass and other rocks are natural materials that contain lots of silicon. The atomic structure of silicon crystals, one atomic nucleus (nucleus) each has 4 valence electrons. A stable atomic nucleus bond is if it is surrounded by 8 electrons, so that the 4 electrons of the crystal atom form covalent bonds with neighboring atomic ions.
Properties and Types of Conductor Materials
Any material that can carry current easily is called a conductor. Meanwhile, which includes conducting materials are materials that have many free electrons in the outer shell of the orbit. These free electrons will greatly affect the properties of the material. If an electrical material has many free electrons in electron orbits, this material has the property of being a conductor of electricity.
Conducting materials have important properties, namely:
- Electrical conductivity.
- Additional temperature coefficient.
- Heat conductivity.
- tensile strength.
- The emergence of thermo electro-motor power.
Meanwhile, citing the Class IX High School Craft module (2018), the following are the types of conducting materials or conductors:
1. Aluminum (AI)
Important properties of aluminum materials, namely:
- Cold forged.
- Does not tolerate table or sea salt.
- Color silver or silver.
- Boiling point=18000C .
- Rho (ρ) = 0.0278.
- •Alpha (α) = 0.0047
2. Copper (Cu)
Some important properties of copper metal, namely:
- Can be plated and corroded when exposed to CO².
- Boiling point = 22360C – 23400C.
- •Rho (ρ) = 0.017.
- •Alpha (α) = 0.0043.
3. Zinc (Zn)
Some important properties possessed by zinc metal, namely:
- Cold forged.
- Not resistant to salt and acid salts.
- Bluish white color.
- • Boiling point = 9070C.
- •Rho (ρ) = 0.0043.
- •Alpha (α) = 0.006.
4. Tin (Sn)
Some important properties possessed by tin materials, namely:
- Shiny clear color.
- Boiling point = 2360C.
- Bluish white color.
- Boiling point = 9070C.
- Rho (ρ) = 0.0043.
- Alpha (α) = 0.12.
In addition to the metal materials mentioned above, there are also other metal materials that are classified as conductor materials for precious metals, such as silver, gold and platinum. This metal material is called a noble metal because this material has a complete number of valence electrons, making it very difficult to carry out other reactions.
Another solid material used for conductors is tungsten which is used for the cathode filaments in electron tubes, incandescent lamps, and high temperature heaters. Bimetallic or often called bimetallic are two types of metals that are joined together.
Its use in the electrical field is very broad, for example contact regulators and regulators are used to keep the hot temperature constant. This bimetal is installed in the heater and its function is to break the circuit when the temperature increases and will reconnect the circuit when the temperature drops.
Atomic Properties of Conductors
1. Band Gap Width
Conductors have a very small and thin valence band gap so that valence electrons in atoms can move easily to other atoms using very little energy. Electrons moving freely from one atomic orbital to another are constantly causing electrical conduction. The orbital left by the electron is called a hole. Subsequent atomic orbitals will experience the same holes as the first orbital due to a reduction in the number of electrons. This process takes place continuously so that electricity arises.
2. Number of Valence Electrons
The electrical conductivity of an electrical conductor is determined by the number of valence electrons present in each atomic orbital making up the electrical material. Electrical conductors with good electrical conductivity have 1 to 3 valence electrons. Within the atomic orbital, a weak force of attraction always exists between the valence electrons and the protons. Valence electrons can move freely even though the electromotive force occurs at a very small value.
The more free electrons in an electrical conductor, the smaller the value of the electrical resistance and the better the electrical conductivity. Conversely, the fewer free electrons in a conductor, the greater the value of the electrical resistance and the worse the electrical conductivity. Types of electrical conductors with good levels of electrical conductivity and low electrical resistance values are copper, aluminum, gold and silver.
Conductor Electrical Properties
1. Conditions of the Electric Field
In a balanced state, the conductor always generates an electric field in a position parallel to the electric conducting surface. In unbalanced conditions, the electric field in the electric conductor will have a component that touches the slanted surface. The electric current on the surface is generated by the field component that touches the surface due to the force on the charge.
Calculation of the amount of electric field generated on the surface of the electric conductor is done by applying Gauss’s law. Electric charge on an electric conductor will move if an electric field is given around it, on an electric conductor. The magnitude of the value of the electric field at all point areas in the electric conductor is zero.
2. Electric Charge Force
In a balanced state, the electric charge on the electric conductor always lies on the surface. Repulsive force will occur if the electric conductor is given an electric charge. The existence of this repulsive force is a result of the nature of the electric charge in the electric conductor which always moves freely easily. The electric charges will continue to repel each other until they reach a state of complete immobility.
Electrical current flow
The amount of electric current flowing is directly proportional to the cross-sectional area of the electric conductor. The larger the cross-sectional area, the greater the conductivity. Conversely, the smaller the cross-sectional area, the lower the conductivity. The difference in the amount of current flowing is due to the electrical conductor having a specific resistance that is proportional to the cross-sectional area.
3. Electrical Resistance
The electrical resistance of most electrical conductors increases with increasing temperature. An increase in temperature causes the movement of electrons to be faster, but the direction of movement is random and irregular, thus increasing the value of the electrical resistance. In electrical conductors that have the same material and cross-sectional area, the value of the electrical resistance is determined by the length of the conductor. This electrical resistance generally uses units of ohms per meter.
4. Electrical Conductivity
Electrical conductors in the form of liquids and solid objects have electrical conductivity. Measurement of the electrical conductivity of an electric conductor is done by quantization. The value of electrical conductivity affects chemical reactions, the number of valence electrons, and the degree of accumulation of electrically conducting ions in solution. Organic compounds have high electrical conductivity, while inorganic compounds have weak electrical conductivity.
5. Magnetic Field
An electric conductor that is powered by an electric current always produces a magnetic field around it. The relationship between the existence of a magnetic field around the conductor became known in the late 18th and early 19th centuries AD.
How Conductors Work
Conductors are materials that allow electrons to flow freely from particle to particle. An object made of a conducting material will allow charge to be transferred across the surface of the object. If a charge is transferred to an object at a certain location, that charge is rapidly distributed over the entire surface of the object.
If a charged conductor is brought into contact with another object, the conductor may even transfer its charge to that object. Transfer of charge between objects occurs more easily if the second object is made of a conducting material. The shape and size of materials affect their conductivity. For example, a thick piece of material conducts better than a thin piece of the same size and length. Temperature also affects conductivity. When the temperature increases, the atoms and their electrons gain energy.
Some insulators such as glass are poor conductors when cold but good conductors when hot. Meanwhile, most metals are better conductors when cold and less efficient conductors when hot.
In electricity, a conductor is a material or substance that allows electricity to flow through them. They conduct electricity because they allow electrons to flow easily in them from atom to atom. Also, conductors allow the transmission of heat or light from one source to another.
Conductors have free electrons on their surface which allow current to flow easily. This is the reason why conductors can conduct electricity. Conductors have free electrons on their surface which allows current to flow easily. This is the reason that electricity transmits freely through conductors.
Practical Uses of Conductors
1. Lightning rod
Lightning rods are used to divert the direction of lightning strikes towards the outside of the building so as not to damage the electrical equipment inside the building. The lightning rod consists of two conducting rods with a pointed end at one end. The building blocks of lightning rods are conductors of electricity. Lightning rod is a long conductor of electricity and has two parts which are located at the ends and are installed at a distance apart. The first part is installed vertically on the roof of the building and the second end is buried in the ground.
The electric charge that collects at the end of the lightning rod is channeled through a cable connected between the conducting rods on the roof of the building and the conducting rods in the ground. The flow of lightning to the ground makes the air around the building always neutral. The existence of a lightning rod makes the environment around the building rarely exposed to lightning strikes.
2. Electrostatic Capacitor
In the field of electrostatics, electrical conductors are used as capacitors that store electric charge. Storage of electric charge is done by providing an electric potential like a battery.
Examples of the Use of Conductors and Insulators
Conductor and insulator materials are often used in everyday life. The types of metal most often used to make these tools include iron, aluminum and copper. Electric stove is a cooking tool that has parts made of conductors and insulators. Another example is a frying pan made of aluminum which is a conductor. This is so that the heat from the fire quickly transfers to the pan so that the food is cooked quickly.
Meanwhile, other cooking utensils, such as Teflon, have handles made of insulators, such as plastic so that our hands don’t get hot when holding them. Then, the iron is also an object that is often used to smooth clothes using heat energy. The heat energy is produced from changes in electrical energy.
Irons are made of conductors and insulators. The conductor properties of the iron are located on the iron base which is made of metal and the insulator properties are located on the top of the iron body and on the plastic handle. This is so that the hands do not feel hot when rubbing clothes.