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series circuits lecture

Added Mar 20, 2020 •

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start working with not only Ohm's law but what happens when we have multiple resisted elements in a circuit I'm just going to call and resistors just to be playing but realized or something up to an electrical system it has resistance that's usually the method by which it'll get the energy out of the electrons move through resistance so if you didn't have me just to keep your refrigerator of it has resisted the lightbulb it has reason when I say resistor and we're doing this time simple volume instead of saying oh we have a resistor a refrigerator and a light bulb and something else that's why I'm just going to pull down resistor how do you deal with them we don't talk so but here's a little bit of a problem a poor let's see a nice video to refresh does a remind you of a couple of the main of that lighten up that you did okay so this is going to differentiate series and parallel circuits going to show you some features what are basic features that you got in that lab is an ordinary 25 watt light bulb with a voltage of 120 volts across it when Justin unscrews it it goes up because the circuit is open before light bulbs on the right are in Siri Chargers with fluff you're off for a phone to complete the circuit when Justin applies 120 volts to the Circuit only 30 volts are across each full so they're both fairly close funny unscrews one ball all four lights go out because no current can pass through the open light bulb four light bulbs are in parallel all four balls will have 120 volts across them that's different before they split up now that he's getting a clue to the top or can pass to the saxophone or I can pass through the third bowl or it can pass through the bottom bow don't half way to the power source when justify the rotation all four lights shine brightly if you unscrew is one of the others keep shining because their current doesn't pass to be open my phone those are amazing things from the basic things we would see what series vs parallel type of circuit they would one day share the voltage in the other day don't need to get the whole thing about the first one which is a series circuit but before that we have to understand equivalent resistance when multiple resistors remember that can just be a resistant element on the circuit can you plug in when multiple resistors are hooked up to a battery and it doesn't need to be at battery can be any power source like wall I'm just trying to simplify things by doing what you did in your lap side of a battery and resistors the battery feels the combined resistance of or what we might call the equivalent resistance equivalent mean equal into the whole thing series circuit a series circuit resistor and then you put another right after another right after if I take one resistor and put another right after it in right after it's a my innocence making a longer resistor or a wider resistor with what does your brain tell you bomber and the other half of the other like making a longer resistor what happens to the resistance in a wire when he gets home I guess you're just what happens to resistance when you put resistors in series it gets more how much more so there's a nice day to think about Siri circuit now will study Monday parallel circuit now parallel circuit if you put one resistor not after the other you put one reason stir next to another hand next to a now am I making a wider or longer resistor wider what happens to resistance when you have a wider lighter goes down we have a method to add resistors in a circuit make resistance go down how bizarre is that you add a resistor in the reasons goes down that's Monday we're going to battle with parallel thirties and you trying to understand that so hard new research you have to be able to do is look at a circuit and this is going to be your knowledge in your you know. This is a series circuit called this was a parallel circuit you'll get a job at casinos in identifying that's not going to be the problem and neither is it the equivalent resistance of a series circuit how easy is that to find the equivalent resistance to Panama will do this in a second with a circuit will apply this to a series circuit use a can figure out things with the battery the ones we have Paris Q are equivalent resistance by adding up resistor one resistor to resist to 3 however many there are. Now we can use that with a voltage of the battery to find the current through the battery so now that we know the equivalent resistance with a battery feeling voltage of the battery because we know v&r we know our push forward and backwards what does that sound Timberland push forward. Percent of your bicycle you're paddling and Aries and visit friends here's your push back resist it. enrich yourself are current but what if you're not told the voltage of the battery what if you're told like the current is going through the battery well then you would use the current and req to find voltage so basically you're going to do one or the other at this point I need to hear to be able to figure out the voltage of the battery or the current the battery to find the other missing piece of the old cloth over the battery now in series the current never split zoeetree the same current as the battery so because the current through each resistor the individual things now are the same we know I to every resist her we also know our read resistor that usually labeled diagram resistor u c r a q there so this isn't talking about battery just talking an individual what resistor in the circuit just one thing in the circuit check to see that all the voltage is used by the resistors add up to the voltage of the battery if you saw that big descendants 120 volt power in it in the series circuit they had four balls get so many volts evolve uses if they split it up 1:20 to put up four ways 30-30-30 and 3 volt to the voltage of the power source and witches are wall to standard okay let's do it unfiltered TV app we have this series circuit if a 1.5 volt Source a 6 Ohm resistor a 2 ohm resistor and a 7 Ohm resistor can you look at this and say one resistor after another after another 9 to get back to the battery yeah to go through all three resistors before you get back that means series let's do the first thing how easy is it to find equivalent resistance in series we want to squeeze eat it so when you get this year what are you doing what's 62 in deck so we have a 15 home equivalent resistance for the circuit as far as the battery power source is concerned it's just like having a single 15 Ohm resistor in a circuit instead of three find the equivalent resistance 1500 and then once we find the equivalent resistance and since we know the voltage of our power source maybe a single battery in a single battery so we can use those two things to find the current through the battery do you see any place in the surf where electrons can say I can go this way or that way no there's no places where current split so truth has to be the same all over the place so if the current through the battery that's what the current through this resistor is play one baby sister sister so now that we know now that we know that each resistor is going to get quite 1 amps of current and we know the resistance of each resistor between old friends now we can throw Ohm's law and each individual resistor find the voltage in uses the first one uses 26 volt the next one has the least resistance it uses the least voltage who has the most resistant he uses the most voltage don't worry about these numbers being like looking the same as to just how so now we see that first one using some voltage the second and the third what do these three add up to is that the voltage provided by the battery sure is right there that's our check for a series circuit the voltage is the combined voltage all of the resistors add up to the voltage of the battery because the voltage split between the resistors in the current is the same at all points these are the what is the saying all pointed voltage split between them that's probably the most important thing for you to understand me the series circuit means I find req then maybe when we do a parallel circuit and the words curve because in a parallel circuit the voltage is the same at all points of the current. So we'll do that one on Monday so that's your homework is pretty easy this weekend

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series circuits lecture

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