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Hello. In this video tutorial I'm going to teach how to measure voltages and intensities.

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We are going to use an online tool and here in the instructions you have the link to go to the

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online tool. If we click on it, a new window appears and we are going to use the lab.

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So click on lab, double click and we are in. So here on the left we have the components we are

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are going to use so for instance I'm going to use a battery so I click and

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drag if I want to rotate the battery I can click here on this side and I can

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rotate it this way you see it now what else do I need I'm going to use a switch

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remember we have studied the components of a circuit so we know what a switch is

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We will also need a bulb, okay? You know what a bulb is. And we are going to use a

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resistor. This is just an example, okay? And we have the four components and we

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will need to connect them. We are going to click and drag pieces of wires

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this way. I click and drag and I click and drag the extremes of the piece of

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wire and this way I can connect everything. The bulb has two connectors, one of them here and the

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other one is here, the red one, okay? If you want to remove a connection, just click on it and click

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on the scissors. Have you seen the scissors? I will repeat. Click on it and if we click on the

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scissors, the connection disappears, okay? So now we have our circuit. And what happens if I close

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the switch. I will click on it. The switch is on.

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Intensity is flowing through the circuit. Can you see the electrons moving?

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You can decide if you want to see them or if you don't want to.

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And if I open the circuit, electrons

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don't move anymore and there is no electricity.

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So I'm going to close the switch again. And now

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because the electrons are moving, we have light on the bulb.

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Perfect, fine. What else can we do with the circuit? We can modify, if we click on the battery, we can modify the voltage. Here I have, I mean, the battery is providing 9 volts. We can modify it to 10, 10.5, 11, whatever.

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We can do the same with the resistance. The bulb has a resistance that can be modified, 9 for instance.

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I can click on the resistor and I can modify its intensity, its resistance, 13 ohms.

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So we can modify the voltage of the battery, the resistance of the bulb, the resistance of the resistor.

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resistor, we can close and open the switch, and the bulb will shine or won't, like at

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this moment, and if we close it, it shines, so we can do a lot of things.

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What else can we do?

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Well, here you have the circuit with the pictures of the elements, they look like they are in

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real life, but you can switch to their symbols.

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If we click here on the right, we have the same circuit, but instead of having the pictures

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of the components, we have their symbols.

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You see the switch?

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We can open and close it, we can modify the resistance of the resistors.

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Every time we want we can go back to the pictures or we can show the symbols.

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We can switch between both of them.

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What else can we do?

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We can use voltmeters to measure the voltage and ammeters, both of them.

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They are here on the right.

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We are studying measuring instruments and here with this exercise I want you to learn

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how to use them.

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For example, the voltmeter, how can we use it?

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We have two wires.

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You already know that the voltmeter has to be connected in parallel.

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It means that if we want to measure the voltage of this resistor, we will place the connectors

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this way.

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and now we have 6.50 volts this is the voltage for the resistor imagine that instead of placing the

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red one here and the black one there we change both of them we have minus 6.50 it means that

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the connectors has been connected the the in the opposite way but this is not a big problem

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anyway if you have a minus here don't worry too much for the moment we will consider that

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is 6.50 and forget about the sign, okay? Forget about the minus, okay? So this is

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the way we measure the voltage of the resistor. And how can we measure the

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intensity that is crossing the resistor? We are going to connect the ammeter, the

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one that is here, and we are going to connect it here in series. If you have

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read the theory, you will know that ammeters are connected in series. So how

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can we do it? We are going to remove this piece of wire, for instance, and we will

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place the ammeter here. So now the ammeter is connected and the same

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intensity that is crossing the resistor is crossing the ammeter and this

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intensity is 0.50 amperes. So now we know that the voltage for this

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resistor is 6.50 and the intensity is 0.50. Does it make sense? Well, let's have a

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look the resistance is 13 ohms the intensity I mean the resistance of the

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resistor the intensity of the resistor is 0.50 and the voltage is 6.50 does it

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make sense yes because if we apply the ohms law we are going to I want to show

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both of them at the same time if we apply the ohms law we know that voltage

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equals voltage here is 6.50. Intensity here is 0.50 and the

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resistance is 13. Okay. Is this equation true? If we multiply 13 by 0.50 is the

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result is 0.50. Let's have a look, and if we multiply 0.50 by 13, the result is 6.50.

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So the Ohm's law is working for the resistor as expected. So we have learned how to measure

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magnitudes using the voltmeter and the ammeter, and we have checked that the Ohm's law is

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working okay so be sure you have understood how to use the voltmeter and diameter because in this

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in the questions of this part of the of this task you will find questions about

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measuring voltages and intensities okay so i hope you have understood everything and

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whatever you need to ask don't hesitate okay bye