Have you heard of the existence of Ohm's law? If you do not have a very clear idea of what this law is, then we recommend that you continue reading this article so that you can expand your knowledge about it and know about its applications in relation to the transmission of electrical energy.
Ohm's law
La Ohm's law It is defined as a relationship that exists between the materials that conduct electricity and the resistance that these materials offer, which causes the electrical energy that passes through that material to be proportional to the voltage that is applied to them. This is an investigation that produced great Importance of Physics. This relationship could be experimentally demonstrated for the first time by the German physicist Georg Simon Ohm who lived between 1787 and 1854.
Statement of Ohm's Law
The researcher Ohm managed to discover at the beginning of the XNUMXth century that the electrical energy that passed through a conductive metal had a directly proportional relationship with the voltage or discrepancy of electrical potential that passed through the metal. That finding by Ohm gave rise to the representation of resistance in circuits.
La Ohm's law explained as an equation, it would be V=RI, where V is the amount of electrical energy expressed in volts, I is the current expressed in amps, and R is the resistance in ohms.
Key Concepts of Ohm's Law
In order to understand the Ohm's law, the definitions of charge, current, and voltage should be explained.
Load
The origin of all charges of electrical energy is found in the conformation of the atom. The charge of an electron is what is known as the primordial unit of charge. The measure with which the charge is expressed is the coulomb (C), to refer to the French physicist Charles Augustin de Coulomb. The charge of one electron is the equivalent of 1,60 x10-19 C. This means that a charge of 1 C is the equivalent of 6,25×1018 electrons.
Drivers
They are those materials through which loads move more easily. They receive the name of drivers and even of superconductors. Because they manage to conduct electrical charges through them. Metals are excellent conductors due to the lack of placement and constant movement of the electrons found in their atomic interior.
One of the metals that is most used as a conductor is copper, particularly in cables and other electrical mechanisms, because it has eleven electrons in its valence. The transparent structure of copper has twelve copper atoms that are linked by their unbound electrons. These electrons are usually described as an ocean of electrons that have the ability to move through the Metal Properties.
- Ohmic conductors: Ohmic conductors are those materials in which the Ohm's law, that is, they show a resistance index that appears constant as long as the temperature is also constant and they do not obey the difference in potential that has been used. This is the case of metallic type conductors.
- Non-ohmic conductors: They are those conductive materials in which it is not fulfilled Ohm's law, that is, that the resistance index is going to change due to the potential difference that is applied. This is the case of some elements present in electronic devices such as computers, cell phones, and many others.
Insulators
Insulators are those materials that are highly resistant to the transfer of electrical charges through them. The valence electrons of insulators, such as with water or wood, are energetically limited and do not have the ability to move freely through the substance.
Electricity cables are an excellent example of the union of a conductor and an insulator, because the core of the cable, which is made of metal, is the conductor of electrical energy while the outer plastic coating material is an insulating material.
Current
Electric current is the effusion of charge that passes through a conducting material in a specified time. Electric current is calculated in amperes (A). An ampere is the equivalent to the effusion of 1 coulomb per second, and its formula would be: 1A= 1C/s.
Voltage
The electrical current that is transported by a conductive material will depend on the electrical value or voltage and the resistance that the conductor opposes to the amount of charge transported.
The electric current is assimilable to the effusion of water. The discrepancy of water pressure within a conduit makes it easier for water to move from high pressure to low pressure. Thus the discrepancy of electrical power measured in volts facilitates the effusion of electrical charges down a wire from an area having a high potential to a low one.
The water pressure is maintained by the effect of a pumping device, and the potential difference for the electrical charge can be maintained by means of a battery.
Electric resistance
Electrical resistance is the degree of inconvenience that electrical charges encounter in moving through a conductive material. If we use the simile of water, the electrical resistance can be compared to the friction of water flowing through a tube or hose.
Thus, a hose or tube that is straight and clean will offer little resistance to the passage of water, on the other hand, a hose or tube that is wrinkled and full of brush will cause the water to be transported more slowly.
Electrical resistance is related to the interaction that occurs in the conducting electrons as they move from one atom to another through the conducting material. The unit of measure used to measure resistance is ohms or ohms, and is represented by the Greek letter omega.
Key points to remember
- The voltage causes the current to move, while the resistance prevents that movement.
- La Ohm's law It is linked to the relationship between voltage and current.
- Circuits or components that comply with the V=IR relationship are called ohmic and show graphs of the current-voltage relationship in linear form and pass through a zero point.
- A rule to help you remember the formula for the Ohm's law is to remember that Victoria was a Queen of England: V=RI