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Electrical circuits - Contenido educativo

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Subido el 18 de junio de 2019 por Isabel L.

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studying electrical circuit from first professor so in each year we study something more with me 00:00:04
that is the new contents so firstly we are going to this is the index and as in something new 00:00:17
there is the Kirchhoff's law. You know it's something that is in the matter. 00:00:32
The matter has been created linking molecules, but molecules also have been 00:00:49
created linking atoms and inside the atoms you have particles which has 00:01:01
electric charge. So electricity is something that is always associated with 00:01:10
matter. If you have matter you have electricity. A little bit different is 00:01:18
that the church can move and in this particular case you can transform electrical energy into 00:01:31
another kinds of electricity. You can also have electricity in some matter, in some elements, 00:01:41
which usually called semiconductors. There are semiconductors because sometimes there 00:01:52
insulators they don't let they don't they don't let the movements of the 00:01:59
churches inside them or in in other circumstances they can be conductors 00:02:08
this is for example one of the of the best samples could be a silicon so in 00:02:15
In this case, for example, silicon can break their links because of temperatures or because you give silicon sun energy. 00:02:26
In this particular case, you can form a hole, which is a positive charge itself. 00:02:39
but you can also have a free electron that can move into the net of the silicon. 00:02:53
You can also have this effect if you interchange one atom in the net of silicon with another particle, 00:03:01
That can be, for example, boron or can be, for example, we have excess of electron or it has a defect of electron, so it has holes. 00:03:15
This is the basis of electronic, because if we put in contact one semiconductor with half 00:03:28
x-axis of electron with another we have defect, the charges tend to move and it's the main 00:03:42
effect of electronic. 00:03:51
The circuits usually have at least five types of elements, which are something that gives 00:04:00
power to the circuit, another element which transforms electricity into another types 00:04:11
of energies. 00:04:23
So in this church you have the main magnitudes that you need to study a electrical circuit. 00:04:28
We have church, we have resistance, which is the opposition of the materials to the 00:04:37
movement of the churches itself, current, load or charge per unit of time, voltat, energy 00:04:46
that you need to move it up into an electrical field, electric power and electric energy. 00:04:55
And you can also have the units, the symbols of some equations that help you to calculate 00:05:08
these magnitudes. 00:05:16
In any circuit you usually have three or five different types of elements, which are something 00:05:17
that provides energy, which usually called generators or batteries, you also have something 00:05:34
that transforms this energy into another type of energy, such as kinetic or light or sound, 00:05:42
something that helps you to control this transformation and you also have something to protect, for 00:05:56
For example, human people or also the active part of the circuit. 00:06:06
Here you also have, for example, some instruments that help you to do measures. 00:06:17
have the symbols of these parts and also the function. Sorry because it is in Spanish, 00:06:26
I haven't translated it in English. Well, the most important law to know and to do calculations 00:06:40
electrical circuit is obviously Ohm's law and it is the Ohm's law is an 00:06:57
experimental law which can be summarized saying that the voltage is you can have 00:07:02
the voltage with this expression. It is very usual that you use a triangle as an 00:07:14
mnemothetnik rule. And here you have an example of application of Ohm's law. You have a very simple 00:07:24
circuit which has been simulated with cocodrille. You already know cocodrille as a tool to design 00:07:41
and simulate circuits so in this circuit you have a battery which is 5 volts and which has a bulb 00:07:54
a bulb or lamp which have a region with you that you don't know the value of the resistance but 00:08:06
But with an amperement you can know that the intensity of current is 50 mA. 00:08:17
So as you have here is the value in ampere. 00:08:31
So you can calculate very easily the value of the resistance in this area. 00:08:37
obviously you usually have more than one element so the the different elements can be associating 00:08:50
into in two ways in serie as you have in this picture which means that the intensity current 00:08:59
is the same for both elements and just application the ohms law and energy balance you can calculate 00:09:09
that the equivalent resistance is the addition of the value of the resistance and using the 00:09:20
Onslaught you also calculate the other parameters. As I said, the resistance is in parallel, 00:09:29
it is in this way, in parallel both resistance are the same voltage but the intensity obviously 00:09:44
divided in this point. So using the balance energy you can calculate the 00:09:57
resistance equivalent with this expression and also the rest of the 00:10:11
parameters. Well, there is something that is not true. The balance doesn't take into 00:10:17
consideration that a part of energy can be 00:10:31
transform it into heat is what usually call Joule's effect so these calculations aren't very very 00:10:38
no they're they're aren't 00:10:51
very exactly exactly but well in in this particular case we can 00:10:56
we can do this calculation because it could be true. Well, it can be explained and can be 00:11:04
summarized in what we usually call the Kirchhoff's law. In a very complex circuit you can have a knot, 00:11:21
which is a point in which you have more than one conductors and in this point the intensity input 00:11:33
and the sum of the addition in the inputs intensities must be the same that the addition 00:11:44
in the output intensities. A mesh with in a mesh you can know the the intensity is 00:11:55
something is a closed circuit but you also have for example branch and 00:12:07
another part of circuit. Very useful in a very compressed circuits for example 00:12:14
this one, in this circuit you have two meshes, you have one branch and we have two nodes, 00:12:27
so if you take into consideration the Kirchhoff's law you can solve this circuit, you can know 00:12:38
intensity in each element and also the voltage in this element. So here you have, for example, 00:12:52
you have for one mesh this expression that is the application of Ohm's law and in the 00:13:02
other this one. So in the end it is a system of equations and it's very easy to solve. 00:13:12
I hope this tutorial has been helpful. 00:13:28
Autor/es:
Isabel Lafuente
Subido por:
Isabel L.
Licencia:
Reconocimiento - No comercial
Visualizaciones:
100
Fecha:
18 de junio de 2019 - 18:18
Visibilidad:
Público
Centro:
IES JAIME FERRAN
Duración:
13′ 40″
Relación de aspecto:
1.78:1
Resolución:
1920x1080 píxeles
Tamaño:
300.36 MBytes

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