POR FRICCIÓN
Una carga eléctrica se produce cuando se frotan uno con otro dos pedazos de ciertos materiales; por ejemplo, se da y una varilla de vidrio, o cuando se peina el cabello.
Estas cargas reciben el nombre de electricidad estática, la cual se produce cuando un material transfiere sus electrones a otro.
Esto es algo que aun no se entiende perfectamente. Pero una teoría dice que en la superficie se un material existen muchos átomos que no pueden combinarse con otros en la misma forma en que lo hacen, cuando están dentro del material; por lo tanto, los átomos superficiales contienen algunos electrones libres, esta es la razón por la cual os aisladores, por ejemplo vidrio, caucho, pueden producir cargas de electricidad estática. La energía calorífica producida por la fricción del frotamiento se imparte a los átomos superficiales que entonces liberan los electrones, a esto se le conoce como efecto triboeléctrico.
POR REACCIONES QUÍMICAS
Las substancias químicas pueden combinarse con ciertos metales para iniciar una actividad química en la cual habrá transferencia de electrones produciéndose cargas eléctricas.
El proceso se basa en el principio de la electroquímica. Un ejemplo es la pila húmeda básica. Cuando en un recipiente de cristal se mezcla acido sulfúrico con agua (para formar un electrolito) el acido sulfúrico se separa en componentes químicos de hidrogeno (H) y sulfato (SO4), pero debido a la naturaleza de la acción química, los átomos de hidrógeno son iones positivos (H+) y (SO4-2). El número de cargas positivas y negativas son iguales, de manera que toda la solución tiene una carga neta nula. Luego, cuando se introducen en la solución barras de cobre y zinc, estas reaccionan con ella.
El zinc se combina con los átomos de sulfato; y puesto que esos átomos son negativos, la barra de zinc transmite iones de zinc positivos (Zn+); los electrones procedentes de los iones de zinc quedan en la masa de zinc, de manera que la barra de zinc tiene un exceso de electrones, o sea una carga negativa. Los iones de zinc se combina con los iones de sulfato y los neutralizan, de manera que ahora la solución tiene mas cargas positivas. Los iones positivos de hidrogeno atraen a electrones libres de la barra de cobre para neutralizar nuevamente la solución. Pero ahora la barra de cobre tiene una deficiencia de electrones por lo que presenta una carga positiva.
POR PRESIÓN
Cuando se aplica presión a algunos materiales, la fuerza de la presión pasa a través del material a sus átomos, desalojando los electrones de sus orbitas y empujándolos en la misma dirección que tiene la fuerza. Estos huyen de un lado del material y se acumulan en el lado opuesto. Así cesa la presión, los electrones regresan a sus órbitas. Los materiales se cortan en determinad formas para facilitar el control de las superficies que habrán de cargarse; algunos materiales reaccionaran a una presión de flexión en tanto que otros responderán a una presión de torsión.
Piezoelectricidad es el nombre que se da a las cargas eléctricas producidas por el efecto de la presión.
El efecto es más notable en los cristales, por ejemplo sales de Rochelle y ciertas cerámicas como el titanato de bario.
POR CALOR
Debido a que algunos materiales liberan fácilmente sus electrones y otros materiales los acepta, puede haber transferencia de electrones, cuando se ponen en contacto dos metales distintos, por ejemplo: Con metales particularmente activos, la energía calorífica del ambiente a temperatura normal es suficiente para que estos metales liberen electrones. Los electrones saldrán de los átomos de cobre y pasaran al átomo de cinc. Así pues, el cinc adquiere un exceso de electrones por lo que se carga negativamente. El cobre, después de perder electrones tiene una carga positiva. Sin embargo, las cargas originadas a la temperatura ambiente son pequeñas, debido a que no hay suficiente energía calorífica para liberar más que unos cuantos electrones. Pero si se aplica calor a la unión de los dos metales para suministrar más energía, liberaran mas electrones. Este método es llamado termoelectricidad. Mientras mayor sea el calor que se aplique, mayor será la carga que se forme. Cuando se retira la fuente de calor, los metales se enfrían y las cargas se disparan.
POR LUZ
La luz en sí misma es una forma de energía y muchos científicos la consideran formada por pequeños paquetes de energía llamados fotones. Cuando los fotones de un rayo luminoso inciden sobre un material, liberan energía. En algunos materiales la energía procedente de los fotones puede ocasionar la liberación de algunos electrones de los átomos. Materiales tales como potasio, sodio, cesio, litio, selenio, germanio, cadmio y sulfuro de plomo, reaccionan a la luz en esta forma. El efecto fotoeléctrico se puede usar de tres maneras:
1.-Fotoemisión: La energía fotónica de un rayo de la luz puede causar la liberación de electrones de la superficie de un cuerpo que se encuentran en un tubo al vació. Entonces una placa recoge estos electrones.
2.-Fotovoltaica: La energía luminosa que se aplica sobre una de dos placas unidas, produce la transmisión de electrones de una placa a otra. Entonces las placas adquieren cargas opuestas en la misma forma que una batería.
3.-Fotoconducción.- La energía luminosa aplicada a algunos materiales que normalmente son malos conductores, causa la liberación de electrones en los metales, de manera que estos se vuelven mejores conductores.
POR MAGNETISMO
Todos conocemos los imanes, y los han manejado alguna que otra vez. Por lo tanto, podrá haber observado que, en algunos casos, los imanes se atraen y en otro caso se repelen. La razón es que los imanes tienen campos de fuerza que actúan uno sobre el otro recíprocamente.
La fuerza de un campo magnético también se puede usar para desplazar electrones. Este fenómeno recibe el nombre de magnetoelectricidad; a base de este un generador produce electricidad. Cuando un buen conductor, por ejemplo, el cobre se hace pasar a través de un campo magnético, la fuerza del campo suministrara la energía necesaria para que los átomos de cobre liberen sus electrones de valencia. Todos los electrones se moverán en cierta dirección, dependiendo de la forma en que el conductor cruce el campo magnético, el mismo efecto, se obtendrá si se hace pasar el campo a lo largo del conductor. El único requisito es que haya un movimiento relativo entre cualquier conductor y un campo magnético.
WAYS OF PRODUCING ELECTRICITY
FRICTION
An electrical charge is produced when rubbed with each other two pieces of certain materials, for example, is given and a glass rod, or when combing hair.
These charges are called static electricity, which occurs when a material transfer their electrons to another.
This is something not yet fully understood. But one theory is that the surface is a material that does not exist many atoms may be combined with others in the same way as they do when they are within the material, therefore, the surface atoms contain some free electrons, this is the I reason insulators, for example glass, rubber, can produce static electricity. The heat energy produced by the friction of friction is imparted to the surface atoms which then release electrons, this is known as triboelectric effect.
FOR CHEMICAL REACTIONS
The chemicals can be combined with certain metals to initiate a chemical activity which will occur electron transfer electric charges.
The process is based on the principle of electrochemistry. An example is the basic wet cell. When in a glass container sulfuric acid is mixed with water (to form an electrolyte) sulfuric acid is separated into chemical components of hydrogen (H) and sulfate (SO 4), but due to the nature of the chemical action, atoms hydrogen are positive ions (H +) and (SO4-2). The number of positive and negative charges are equal, so that all the solution has a net zero charge. Then, when introduced into the solution bars of copper and zinc, these react with it.
The zinc combines with the atoms sulfate, and since these atoms are negative, rod zinc transmits zinc ions positive (Zn +); the electrons from the zinc ions are in the mass of zinc, so that the zinc bar has an excess of electrons, or negatively charged. Zinc ions combine with the sulfate ions and neutralize them, so that now the solution has more positive charges. Positive hydrogen ions attract electrons free copper bar to neutralize the solution again. But now the copper bar has a deficiency of electrons so it has a positive charge.
PRESSURE
When pressure is applied to some materials, the pressure force of the material passes through its atoms, dislodging electrons from their orbits and pushing in the same direction having force. These escaping from one side of the material and accumulate on the opposite side. So the pressure ceases, the electrons return to their orbits. The materials were cut into shapes determinad to facilitate control of the surfaces to be loaded, some material reacted at a pressure of flexion while others will respond to a torque pressure.
Piezoelectricity is the name given to the electric charges produced by the effect of pressure.
The effect is most noticeable in the crystals, such as Rochelle salt and certain ceramics such as barium titanate.
HEAT
Because some materials release the electrons readily accepts and other materials, may have electron transfer when brought into contact two different metals, for example, with particularly active metals, the heat energy from the environment at normal temperature is sufficient for these metals freed electrons. The electrons will leave the copper atoms and pass into the zinc atom. Thus the excess zinc acquires electrons so that becomes negatively charged. Copper, after losing electrons has a positive charge. However, the loads arising at room temperature are small, because there is not enough heat energy to release more than a few electrons. But if heat is applied to the union of the two metals to supply more energy, liberate more electrons. This method is called thermoelectricity. The higher the heat applied, the greater the load to be formed. When you remove the heat source, the metal cools and charges soar.
BY LIGHT
The light itself is a form of energy and many scientists consider it consists of small packets of energy called photons. When photons of a light beam incident on a material, they release energy. In some materials the energy from photons can cause the release of some electrons from atoms. Materials such as potassium, sodium, cesium, lithium, selenium, germanium, cadmium and lead sulfide, react to light in this way. The photoelectric effect can be used in three ways:
1.-Photoemission: The photon energy of a beam of light can cause the release of electrons from the surface of a body are in a vacuum tube. Then a board collects these electrons.
2.-Photovoltaic: The light energy is applied on one of two plates joined, causes the transfer of electrons from one plate to another. Then the plates opposite charges acquired in the same way as a battery.
3.-Photoconduction. - The light energy applied to some materials that are normally poor conductors, causes the release of electrons in metals, so that these become better drivers.
BY MAGNETISM
We all know the magnets, and have handled occasionally. Therefore, there may be observed that in some cases, the magnets attract and repel otherwise. The reason is that the magnets have force fields that act on each other reciprocally.
The strength of a magnetic field can also be used for moving electrons. This phenomenon is called magnetoelectricidad, based on the generator produces electricity. When a good driver, for example, copper is passed through a magnetic field, the field strength supply the energy needed for the copper atoms release their valence electrons. All the electrons move in a certain direction, depending on the manner in which the conductor cross the magnetic field, the same effect is obtained if the field is passed along the conductor. The only requirement is that there is relative movement between any conductor and a magnetic field.
FRICTION
An electrical charge is produced when rubbed with each other two pieces of certain materials, for example, is given and a glass rod, or when combing hair.
These charges are called static electricity, which occurs when a material transfer their electrons to another.
This is something not yet fully understood. But one theory is that the surface is a material that does not exist many atoms may be combined with others in the same way as they do when they are within the material, therefore, the surface atoms contain some free electrons, this is the I reason insulators, for example glass, rubber, can produce static electricity. The heat energy produced by the friction of friction is imparted to the surface atoms which then release electrons, this is known as triboelectric effect.
FOR CHEMICAL REACTIONS
The chemicals can be combined with certain metals to initiate a chemical activity which will occur electron transfer electric charges.
The process is based on the principle of electrochemistry. An example is the basic wet cell. When in a glass container sulfuric acid is mixed with water (to form an electrolyte) sulfuric acid is separated into chemical components of hydrogen (H) and sulfate (SO 4), but due to the nature of the chemical action, atoms hydrogen are positive ions (H +) and (SO4-2). The number of positive and negative charges are equal, so that all the solution has a net zero charge. Then, when introduced into the solution bars of copper and zinc, these react with it.
The zinc combines with the atoms sulfate, and since these atoms are negative, rod zinc transmits zinc ions positive (Zn +); the electrons from the zinc ions are in the mass of zinc, so that the zinc bar has an excess of electrons, or negatively charged. Zinc ions combine with the sulfate ions and neutralize them, so that now the solution has more positive charges. Positive hydrogen ions attract electrons free copper bar to neutralize the solution again. But now the copper bar has a deficiency of electrons so it has a positive charge.
PRESSURE
When pressure is applied to some materials, the pressure force of the material passes through its atoms, dislodging electrons from their orbits and pushing in the same direction having force. These escaping from one side of the material and accumulate on the opposite side. So the pressure ceases, the electrons return to their orbits. The materials were cut into shapes determinad to facilitate control of the surfaces to be loaded, some material reacted at a pressure of flexion while others will respond to a torque pressure.
Piezoelectricity is the name given to the electric charges produced by the effect of pressure.
The effect is most noticeable in the crystals, such as Rochelle salt and certain ceramics such as barium titanate.
HEAT
Because some materials release the electrons readily accepts and other materials, may have electron transfer when brought into contact two different metals, for example, with particularly active metals, the heat energy from the environment at normal temperature is sufficient for these metals freed electrons. The electrons will leave the copper atoms and pass into the zinc atom. Thus the excess zinc acquires electrons so that becomes negatively charged. Copper, after losing electrons has a positive charge. However, the loads arising at room temperature are small, because there is not enough heat energy to release more than a few electrons. But if heat is applied to the union of the two metals to supply more energy, liberate more electrons. This method is called thermoelectricity. The higher the heat applied, the greater the load to be formed. When you remove the heat source, the metal cools and charges soar.
BY LIGHT
The light itself is a form of energy and many scientists consider it consists of small packets of energy called photons. When photons of a light beam incident on a material, they release energy. In some materials the energy from photons can cause the release of some electrons from atoms. Materials such as potassium, sodium, cesium, lithium, selenium, germanium, cadmium and lead sulfide, react to light in this way. The photoelectric effect can be used in three ways:
1.-Photoemission: The photon energy of a beam of light can cause the release of electrons from the surface of a body are in a vacuum tube. Then a board collects these electrons.
2.-Photovoltaic: The light energy is applied on one of two plates joined, causes the transfer of electrons from one plate to another. Then the plates opposite charges acquired in the same way as a battery.
3.-Photoconduction. - The light energy applied to some materials that are normally poor conductors, causes the release of electrons in metals, so that these become better drivers.
BY MAGNETISM
We all know the magnets, and have handled occasionally. Therefore, there may be observed that in some cases, the magnets attract and repel otherwise. The reason is that the magnets have force fields that act on each other reciprocally.
The strength of a magnetic field can also be used for moving electrons. This phenomenon is called magnetoelectricidad, based on the generator produces electricity. When a good driver, for example, copper is passed through a magnetic field, the field strength supply the energy needed for the copper atoms release their valence electrons. All the electrons move in a certain direction, depending on the manner in which the conductor cross the magnetic field, the same effect is obtained if the field is passed along the conductor. The only requirement is that there is relative movement between any conductor and a magnetic field.
