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CIRCUITOS - Contenido educativo

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Subido el 13 de abril de 2020 por Isabel L.

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well we are going to take into consideration that in a motor you can 00:00:14
change the source of rotation if you change the polarity in a battery. What I 00:00:23
trying to say is for example if I have a very simple circuit with just only one 00:00:30
motor like this and we have two now that are the same circuit but in this one we're going to change 00:00:38
the polarity of the battery so we have two circuits 00:01:25
that are the same, but in this one, the polarity has this sense, so the motor rotates in this sense, 00:01:34
and in the other one, the polarity of the battery is changing, so the sense of rotation also is inverse. 00:01:51
So, we can solve the problem if we are able to join these two circuits. 00:02:03
To do that we need a special switch. 00:02:14
So we are going to stop and we are going to transfer the circuit. 00:02:22
have one we can do with the battery it is possible but there isn't just only 00:02:34
one solution of this problem you can choose you can find different solution 00:02:46
I'm going to give the one that I think is the best is using this type of switch 00:02:52
this type of switch have two positions as you can see here this is one position 00:03:01
and this is the other position so this kind of switch let us to join both 00:03:12
circuits so we have the two position and now we have there's only one motor so in 00:03:24
this position we join our motor in this way so we have sorry in this in this way 00:03:40
so we have one sense of rotation so if I change this position 00:04:12
don't worry sometimes happen I need to change also the polarity so now I have 00:04:22
the other sense of rotation so in this position we have one 00:04:43
sensor rotation and in the other we have the opposite. So it's one solution 00:04:50
you also can do with two batteries and different switches, but from my point of 00:04:56
view this is the best solution of this problem. Well, the next one. To understand 00:05:05
the importance of the diode LED and how it works. We can do two different circuits 00:05:19
similar to the motor, but in this case we need at least one resistor. The best 00:05:31
value for the resistor is 220 and very careful because this is the symbol of 00:05:46
lead and this is the most important thing in this case so we have the 00:06:07
symbol of lead and indeed is a little bit more complicated that what I'm going 00:06:12
to explain for you but I don't know I think is it's difficult to understand 00:06:21
well if at the same we are going to copy and paste the same but changing changing 00:06:30
the polarity well what happens in the polarity is that it the left works 00:06:50
perfectly but if the polarity is inverse the LED doesn't work. It's what I want to learn 00:07:18
no more because it is indeed more complicated. For example we're going to 00:07:27
measure the intensity current in both circuits. Well something similar 00:07:36
happens with the left. If I have a simple circuit with a battery and resistor 00:08:28
this is the resistor of about 220 you can find this kind of circuit a lot of 00:08:39
them searching for information on the Internet. So the circuit itself is really 00:08:49
really easy. The problem is not a circuit, the problem usually is that you can 00:08:57
understand what happened with the circuit, but the circuit itself is really 00:09:04
easy. Firstly, in a diabolos we can have different colors and in each color is 00:09:10
also difference the condition that they they must work but in any case if you 00:09:39
have a good son of working for the left and the the voltage in the less resource 00:09:48
is always the same is always about a oh seven a volts so we are going to do 00:09:58
two different circuits with the same diode and the difference between them is 00:10:11
just only the polarity in the battery. The only difference between these two 00:10:24
circuits is the polarity of the battery. What happened? In the first 00:10:55
case the diode works perfectly but in the second it doesn't it's enough that 00:11:09
you for the moment understand this do you do you don't need to understand not 00:11:20
But if you want, if I connect a voltimeter in parallel with the diodo, in each case, you can know the voltage in this case. 00:11:28
so if you have the voltage you also can know the intensity current so a good 00:12:15
exercise for you can be to use the Ohm's law in this case in in each case 00:12:38
and for the moment is enough for you that if you change the polarity the 00:12:47
other doesn't work it's enough for you if you want you want to do something 00:12:54
more you must use Young's law to understand this case because in this 00:13:00
case is is quite different other thing that can be good a good exercise if you 00:13:09
want if try to change try to change the diode and know what happened with the 00:13:18
intensity current and the voltage for example if I use instead a red one if I 00:13:30
use a red one, you can see that the values are different. So depending on the 00:13:39
diodes, the values of intensity, current and voltage are 00:14:03
different. Well, can be interesting also if you want, but for the moment is enough 00:14:10
with this information because as you can imagine it is more complicated than this 00:14:20
so finally the resistor the value of the resistor well I added to you apart from 00:14:32
the video with the difference circuit I'm going to add it a document in which 00:14:42
I explain the third question of this exercise I hope it can be useful for you 00:14:52
Thank you so much. In the last exercise we must know the value of this resistor using the 00:15:03
color code. So we have to know the nominal value we have the three 00:15:20
first band color band first is yellow so digit 4 second is orange so digit 3 and 00:15:27
third is red so digit 2 so take if we have if we take into consideration the 00:15:39
position of the band, it is very easy to know that the value of the resistor is 4300 ohms, 00:15:52
or what is the same, 43 kilos. 00:16:05
The fourth band is tolerance. 00:16:12
this case is silver so its value is 10% it means that our resistor is between 00:16:15
the its upper value which is its value plus the 10% of its value in this case 00:16:28
the 10% is 430 and the lower value of the resistor so in our case is 10% of 00:16:41
thousand three hundred so 430 so our resistor is between its upper value and 00:17:00
And its lower value, its upper value is 4,300 plus 330. So the result is 4,730 is its upper value. 00:17:14
And its lower value is 4300, but you must to pick up the 10%. 00:17:57
So, its lower value is 3080.70, and that is the exercise. 00:18:23
Idioma/s:
en
Autor/es:
Isabel Lafuente Reboredo
Subido por:
Isabel L.
Licencia:
Reconocimiento - No comercial
Visualizaciones:
12
Fecha:
13 de abril de 2020 - 19:25
Visibilidad:
Público
Centro:
IES JOSÉ GARCÍA NIETO
Duración:
18′ 52″
Relación de aspecto:
1.78:1
Resolución:
1920x1080 píxeles
Tamaño:
205.21 MBytes

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