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Block 6 hints for the exercises - Contenido educativo

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Subido el 16 de abril de 2023 por Beatriz T.

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Block 6 hints for the exercises

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These are some ideas for block 6. In exercise 1 remember the two formulas that you have to use. 00:00:00
When you have a series-parallel combination like in question C, first you have to solve the branches 00:00:07
that are in parallel. For this you have two resistors that are in series of 50 ohms and 00:00:12
then solve the two branches that are in parallel. Here you have the results. This is the first 00:00:18
operation you have to do and you get this result but this is not the equivalent resistance is the 00:00:25
inverse that is the investor you have to look for this button in your calculator that says to you 00:00:32
which is the inverse of a fee of a number finally you add these two figures 10 and 15 in question 00:00:43
one F the first thing you have to do is to add these two figures 10 and 30 you 00:00:54
get this preliminary result 40 ohms then you have two branches in parallel there 00:01:01
are 40 ohms each use the formula of parallel and parallel resistors and then 00:01:10
you have the equivalent resistance here that is 20 ohms and finally add these three figures and 00:01:21
you will get the result exercise two is more complicated first in my opinion you have to 00:01:27
number all the resistors resistor one two three four and five the first thing you have to do is 00:01:36
to calculate equivalent resistance to do so you have to add these two resistors that are in series 00:01:47
20 and 10 and then you have two branches one there are three and four and five so make this 00:01:55
calculation 1 divided by 60 plus 1 divided by 30 you get this result and the inverse is 20 ohms 00:02:07
then you can add the three figures 100, 150, and this 20 ohms. 00:02:16
So your equivalent resistance is 270. 00:02:22
Next step is to calculate the intensity through all the CKIT. 00:02:25
Remember that this is the intensity that is flowing in this branch and also in this branch. 00:02:34
the total intensity is the voltage of the cell divided by the equivalent resistance so you get 00:02:41
the result and then they are asking you all the intensities that are flowing through each resistor 00:02:47
in resistor one you have the intensity of the c kit in resistor two you also have it but here 00:02:56
it's divided in two branches to calculate it through the arms law you need to know the voltage 00:03:03
that is left in this resistor we know that we have 10 volts that is being used through resistor 1 00:03:11
resistor two and here between in resistor three you have the same voltage between these two points 00:03:24
and between this and this so what i'm going to do is to calculate voltage in resistor one 00:03:34
in resistor two and then the left is um the amount that is left between these two points 00:03:42
is going to be resist the voltage in resistor three here you have the calculations so voltage 00:03:53
in resistor one is the total intensity by resistor one so you have 3.7 volt in resistor voltage in 00:04:00
resistor 2 is 5.6 volt you add these two figures and you get that you are using already 9.25 volts 00:04:08
so the remaining that i have is 0.75 volt so the voltage in resistor three is 0.75 volts 00:04:18
with the ohm's law you can calculate the intensity that is going through this resistor 00:04:36
voltage divided by resistance 0.75 volts divided by 60. you have this uh intensity the intensity 00:04:43
in the other two resistors is equal because they are in series in the branch that is in 00:04:53
parallel with resistor 3 and you can calculate making this difference the intensity that you 00:04:59
have in in the origin in your in your cell and you make this subtraction with 00:05:06
the intensity number three and then you can get these results check that you 00:05:15
have these results finally in all your resistors in exercise three we have two 00:05:22
resistors that are in series with three in parallel. The first thing to do is to 00:05:33
calculate equivalent resistance. Here we have to 00:05:38
calculate these three branches that are in parallel and this is the operation 00:05:48
you have to do. The three resistors are equal so the result is 3 divided by 30 00:05:54
but the equivalent resistance is the inverse that is 30 divided by 3 that is 10 ohms so you add this 00:05:59
figure to the other two 200 and 100 and the equivalent resistance is 310 ohms um as these 00:06:06
two resistors are in series the intensity that is going to be the same and equal to the total 00:06:16
intensity we calculate as always with the voltage of the cell divided by equivalent resistance and 00:06:22
is 0.08 ampers. With this figure we can calculate the voltage that is 00:06:29
being used by these two resistors 1 and 2. You have to calculate exactly the same as you have 00:06:39
on in the previous exercise with the ohm's law voltage in one is the intensity by resistance 00:06:45
is this figure and voltage in two is this figure so you can calculate the addition of these two 00:06:53
voltages and the remain with the voltage of the cell that was 25 volts is the voltage that you 00:07:00
have involved in the resistor number three um now you have the voltage that you have in this 00:07:06
in these three uh here in these three resistors because it's the same the voltage in resistors 00:07:15
three four and five as they are equal and they are in parallel is the same and finally you have 00:07:22
to calculate the intensity that is going through these three resistors but it's this is very easy 00:07:28
because the total intensity that is coming through this way is divided into these three branches as 00:07:33
the three resistors are equal the intensity through them is going to be the same and it's 00:07:39
going to be the third of the total intensity so finally you have here the results that we're 00:07:44
asking in the exercise number four you have two branches in parallel and one resistor number one 00:07:51
that is of one kilo ohm be careful uh i think this was a mistake from the book because it's 00:08:02
uh very big well uh first of all as always a total equivalent resistance 00:08:08
are these two figures in each brand so you have three plus two five and four plus five nine volts 00:08:14
so uh these two in parallel uh one divided by you have this result that is 0.31 00:08:20
and the inverse of this is 3.21 that you have to add to the resistor number resistance number one 00:08:28
that is one thousand ohms so this is your strength sphere of the equivalent resistance the total 00:08:36
intensity it's always voltage divided by resistance you have this figure almost nine milli amperes you 00:08:44
can um seek out it well the third question is the voltage across is each resistor to calculate it 00:08:52
we need to know uh which is the voltage that's be it's being used by resistor one and you can 00:09:04
calculate because you know that the intensity that is flowing through this resistor is the 00:09:11
total intensity so you multiply it whatever for by the value of the resistance and you have 8.97 00:09:16
volts that is almost the whole uh nine volts that you have in the in the cell so 00:09:27
So the remaining voltage, that is this amount, that is 29 millivolts, is used by these two branches. 00:09:38
But the voltage in each of them is not the same because the four resistors are different. 00:09:48
What we have to calculate now is the intensity that is going through each of the branches with this value of 29 millivolts. 00:09:55
Then we can calculate with the Ohm's law. Well, I have done it with intensities divisor, but you can also calculate it with the Ohm's law. 00:10:04
You have these two intensities making this average here and finally you can calculate the voltage in each of the resistors. As you can see the voltage in these four resistors is really small and the intensities are equal to light 2. 00:10:21
Autor/es:
BEATRIZ TORREJÓN
Subido por:
Beatriz T.
Licencia:
Reconocimiento - No comercial
Visualizaciones:
105
Fecha:
16 de abril de 2023 - 20:30
Visibilidad:
Público
Centro:
IES CERVANTES
Duración:
10′ 47″
Relación de aspecto:
1.78:1
Resolución:
1280x720 píxeles
Tamaño:
113.15 MBytes

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