Basics of Ohm's Law, Volts, Amps, Ohms, and Watts Explained

hey guys Jade here at word of advice TV and I believe that every technician every good technician should know what Ohm's law is and how to use it now if you're watching this video and Ohm's law sounds like a foreign language to you you're in the right place stay tuned but if you're a veteran technician and Ohm's law is your second language then that's okay consider this as a refresher and at the end of the video if you have any Corrections to say about what you saw in this video please let us know in the comments below and because I like to keep things simple I'll try to keep this explanation as simple and basic as possible so let's begin Ohm's law what is it it's basically this little formula right here this own part all that means is a guy who came up with this concept Ohm's law his last name was ohm so now it's named after him and I don't know if this is just a science or a physics thing but it seems like that happens a lot the guy who came up with boats his last name was Volta the guy who came up with amperes or amps his last name was ampere and Watts are not on here but can you take a wild guess what the last name is of the guy who came up with Watts I know it's hard to believe but his last name is what but anyway back to the formula there's actually quite a few different ways to draw this in fact this is the simplified version there's a bigger chart of this and I'll include a picture of that as well but these two right here are the most common ones so this right here is the Ohm's law pie and this one is the Ohm's law triangle they're both the same exact thing when this concept or drawing was first drawn V is what it started out with for voltage and somewhere along the line they decided to change it to electromagnetic force which is the same thing as voltage so they switched it to an E but they're basically the same exact thing I guess the people that made these drawings are very considerate so if you absolutely hate circles you can use a triangle they're both the same so V or e stands for voltage I which means intensity stands for current which is usually measured in amps or amperes and R stands for resistance which is usually measured with ohms which is this Omega symbol right here that stands for ohms the purpose of Ohm's law that formula right there is very simple if a person has two out of the three of the values they will always be able to figure out the third one so if you have the volts and the resistance but you don't have the amps of a component or a circuit you can figure that out using this formula right here and before I go into examples of how I would use this formula just really briefly I want to go over what voltage current and resistance actually is just in simple terms so voltage is what makes electricity move it's basically the driving force the stuff that pushes electricity through some people refer to it as pressure or tension so voltage is basically what makes the electricity or electrons move and the scientific explanation of this is pretty long and if I go into that this video will no longer be simple but luckily that's not needed for this formula at all the explanation or the science behind it so we're not even going to go there and next up is current current is how much electricity is flowing through a given point so basically the volume or how much electricity is flowing through and resistance is something that resists the flow of electricity and one example of that is a piece of wire just to make resistance a little bit more cleaner a piece of wire is made out of two things one is the insulation around the wire and the inside of the wire is typically made out of copper metals have a very low resistance to electricity so they're perfect to use as conductors to conduct electricity whereas plastic or rubber has a very high resistance to electricity so it's perfect to use as insulation so none of the electrons get out and this right here is an insulated connector which is made out of plastic once again for the same reason because it has very high resistance to electricity and another form of resistance is electrical loads such as a motor a light bulb or like a heating element and I realized that this probably is starting to sound a little bit confusing which is why most people when they're trying to explain this concept bring up the water analogy so I'm going to go ahead and touch on that as well because electricity and water the way both of them work is pretty similar so that helps better understand all of this so I'm thinking about water you know how we have electrical outlets all over the house you plug something in and it gets turned on same with water you have water faucets all over the house you turn the valve on and water comes out so there's two things needed to make that work one is the water itself and two is water pressure or pressure to push the water through the pipes and out the water faucet same with electricity it's at the outlet and you need voltage right here voltage is the pressure that pushes electricity through so water pressure and voltage is essentially the same thing as for current current is how much electricity is flowing through so in the example of water that would be the volume of water or how much water is flowing through the pipes now the bigger diameter the water pipe is the more water it can flow through and same with current the thicker the gauge of wire is so the thicker this wire is the thicker the copper part is the more electricity or a current more amperage can go through that piece of wire as for resistance I think a good example of that is the shower valve in your shower so the water pressure is pretty high going up to the shower valve and then that pressure drops as it's forced through that restriction and the pressure drops and there's a lot of little streams that come out and if you apply that to electrical currents an electrical load for example a motor would be like that shower valve so there's power going into the motor and that the motor to start running and as with water pipes if you apply too much pressure to a water pipe it will burst same with current if you apply too much electrical current to a wire so if the wire is not rated for that amount of amps or a current to go through it that wire will melt or burn so hopefully that water analogy helps paint a better picture of what voltage current and resistance actually is and now let's go back to our little formula right here and how to actually use it so like I was saying earlier if you have any of the two values from that little formula you can always figure out the third so for example if you have the voltage and the resistance of a motor then you can figure out the amperage by using this formula or if you have the voltage and the amperage but you don't have the resistance you can use this formula to figure it out if you don't have the voltage you can cover up the V all you would have to do is do I times R to get you your voltage so amps times resistance would get the voltage now if you don't have the resistance you can cover up the resistance and since they're on top of each other like that that's division so volts divided by amperage would get you the resistance now if you're looking for the amps you can cover that up and as you can see volts divided by resistance would get you your amperage so let's do a couple examples of that so let's draw an Ohm's law pie right over here do our little sections and let's say we have a single-speed blower motor that is rated at six am so we can put the six where the eye is and we know that the voltage for it is a hundred and fifteen volts but we don't know what the resistance is so by using this formula it would be our resistance equals 115 / 6 which would equal 19 point 17 ohms do a little ohm symbol right there so that would be our 19 point 17 ohms so let's do just one more example let's say we're looking at a contactor coil in an air conditioner so let's draw us another little own pi Ohm's law PI I should say split up our sections so let's say instead of resistance what we're missing is the amperage so we can put I right here intensity current or amps same thing I write here and let's say the resistance of our contactor is about 18 ohms that's pretty normal for a good contactor coil and the voltage for it coming from the transformer let's say that is 24 volts so in order to figure out our amperage we would need to divide 24 by 18 or basically divide the voltage by the resistance so I our amps equals 24 divided by 18 this marker is not even on all sides so it's looking kind of goofy okay 24 divided by 18 which equals 1.33 amps so amps is 1.33 amps right there so that is how you use the Ohm's law formula to figure out your missing value and usually you never really have to figure out the voltage that one's pretty obvious but just to show an example of that one as well let's draw us one more pie let's say what we're missing this time is the voltage our resistance is going to be 25 and our amperage will be 4.6 so to figure out the voltage we would need to do amps times the resistance so in our case it would be V equals four point six times 25 which would come out to 115 volts and just for the sake of simplicity let's just write these little formulas out so voltage equals I times R our resistance would be V divided by I and our amperage would be V divided by R or voltage divided by resistance so that is the Ohm's law formula and examples of how to use it and one thing I did not cover yet is watts so let's go ahead and add watts to the list here and that will be the last thing we talked about so a watt is a measurement of the rate of energy transfer now that kind of sounds like a mouthful so in simple terms if we go back to our water analogy and what would be like the speed of the water going through the pipe how fast it's going through so basically a rate of transfer how fast that electricity is going through and there is another formula for figuring out the watts and it's pretty simple I'm gonna go ahead and write that one down as well so it's P power which is the same thing as watts P equals V times I so voltage times amps will give you your wattage so for example let's just use W for watts equals let's say that our voltage is 120 volts times seven amps that would equal to 840 watts so that is the formula used to figure out watts and just a fun fact with watts let's get this race in or out of the way one horsepower this is not related to any of this but just a fun fact one horsepower equals 746 watts so that's kind of cool to know and while we're on fun facts let's go back to current for a second so the way we measure current and the technical field is by using an amp clamp so the amp clamp is basically measuring the amount of current or an amount of electrons flowing through any point on the wire in one second so my question to you is how much electrons electrons are really microscopic little things how much electrons are flowing through that one point in the wire in one second the answer is six point two four times 10 to the 18th power now that might not seem very impressive so let's actually write this out so you can actually understand how much electrons were talking about here there you go now that looks more impressive so basically that many electrons flow by your meter in one second that would equal to one amp well guys and as you can see I ran out of room on the whiteboard which is okay because that is all I wanted to share today hopefully you've got some good information out of this this has been helpful for you or at the very least you've got some fun facts out of it don't forget to visit the comments section and match the like button and the way out thank you so much for watching this video and I'll see you next time and if you are still here and not in the comment section below did you know that the little white M that is on M&Ms is actually made out of edible paper don't believe me I'll prove it to you watch this [Music] [Music] [Music] [Music] you

Channel: Word of Advice TV

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Keywords: ohms law, ohm's law, ohm's law practical, ohm's law formula, ohm's law basic, ohm's law experiment, ohm's law explained, ohm's law explained simply, what is ohm's law, what is ohms law, volts, amps, ohms, what are ohms, what are amps, what are amps and volts, what are amps and watts, how electricity works, amps explained, Ohm's law triangle, ohm's law traingle explained, how to use ohms law, how to use ohm's law, how to use ohms law wheel, word of advice tv

Id: sILl7p_J1UU

Length: 16min 39sec (999 seconds)

Published: Wed Feb 05 2020