HellasTechn
- Apr 14, 2013
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I accidently came across this video and after watching it i think that what says is correcrt.
What do you think ?
What do you think ?
HellasTechn
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Voltage and Resistance makes Amperage. isnt that correct ?
You have no idea how many people i have met that dont really understand what current is and how it is affected by voltage and resistance.
as far as what he says at 05.30 of the video i dont fully agree. It is not all about fixing circuits but also about creating circuits
You have no idea how many people i have met that dont really understand what current is and how it is affected by voltage and resistance.
as far as what he says at 05.30 of the video i dont fully agree. It is not all about fixing circuits but also about creating circuits
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Yeah, just what we need... dumb down the math and forget the algebra. This is how you teach kids to diagnose and troubleshoot problems? This is critical thinking?
I don't have a problem with his approach. He is specifically stating that from his experience with a specific subset (young, under-educated adults) that converting the equation to things they can relate to achieves a greater understanding of the material. He is being pragmatic in stating that these people will not know what an electromotive force is vs. voltage is something they may better understand.
As for dumbing down, well there is truth in that Hop. Unfortunately, physics is not taught in every high school. I took it in senior year of high school and sadly did not do well in it despite having done well in other math and science courses. Call it senioritis or a very boring, droning professor - but boy, do I feel cheated now ;-)
As for dumbing down, well there is truth in that Hop. Unfortunately, physics is not taught in every high school. I took it in senior year of high school and sadly did not do well in it despite having done well in other math and science courses. Call it senioritis or a very boring, droning professor - but boy, do I feel cheated now ;-)
First, he is wrong from the start. Ohm's law in not V=IR and all its variations. R=V/I is the definition of resistance, not Ohm's law. Ohm's law is the electrical linearity of a material. It is a property of a material, not a definition or method of determining V,I, or R. The definition R=V/I is always correct, but it is not Ohm's law. A material like tungsten wire that carries twice the current at twice the voltage is termed ohmic, and follows Ohm's law. A diode whose current varies exponentially with voltage is termed nonohmic and does not follow Ohm's law.
Second, he uses technical slang like "current flow" which means "charge flow flow", and makes no sense. He should say that current exists or is present. Charge flows, but current does not. Charge does not flow twice.
Third, I don't think using alternate symbols for the electrical quantities is going to scramble any student's brains. Learning more than one name for a quantity is not going to defeat even a beginner.
I see that his website plugs some courses that cost much and appear to teach little. That is my opinion.
Ratch
I'm not fond of this at all...
He's dumbing it down, but going too far in my opinion.
If you can't teach someone how to rearrange V=IR ( or E = I R ) to be able to solve for the missing piece, then they should not be working with electricity.
This formula is a relationship that solves for one unknown when you have two known values with ohmic materials (as stated above). Perhaps this is a good internal training video for an after-school part-time job.
Voltage and Resistance make Amps... :s
My least favourite sentence I think.
When I try to explain this kind of thing to my less educated friends, I try to use water analogies. Everyone knows what happens to a hose when you pinch it. Smaller hoses let less current through than larger hoses... and if you really want to put a bunch of current through something, you need to ramp up the voltage or get a bigger hose. (You can also unscrew that sprinkler on the end)
He's dumbing it down, but going too far in my opinion.
If you can't teach someone how to rearrange V=IR ( or E = I R ) to be able to solve for the missing piece, then they should not be working with electricity.
This formula is a relationship that solves for one unknown when you have two known values with ohmic materials (as stated above). Perhaps this is a good internal training video for an after-school part-time job.
Voltage and Resistance make Amps... :s
My least favourite sentence I think.
When I try to explain this kind of thing to my less educated friends, I try to use water analogies. Everyone knows what happens to a hose when you pinch it. Smaller hoses let less current through than larger hoses... and if you really want to put a bunch of current through something, you need to ramp up the voltage or get a bigger hose. (You can also unscrew that sprinkler on the end)
I prefer to think of it as a mathematical relationship where I can choose the dependent variable at will.
HellasTechn
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This part i dont understand.
Isnt the movement "flow" of valence electrons "free electrons" what we call electrical current ?
I think we can say Voltage is present but current is not present untill a circuit is complete right ?
Current needs a conduction path, but that is not what I am gripping about. Didn't I make it clear that current is charge flow? Therefore current flow literally means charge flow flow. What is there about that phrase current flow that you don't understand?
Ratch
I will offer that perhaps since he is not a native english speaker he may not grasp what you are pointing out.
Also, the term "current flow" is so often used that it has become understood amongst us lay people. (A quick web search shows that is not just the lay folk...)
The word "current" as defined by Merriam below, is redundant in use when people say "current flow" since this is equivalent to saying "(the flow of electricity) flow"
current
noun
: a continuous movement of water or air in the same direction
: a flow of electricity
: an idea, feeling, opinion, etc., that is shared by many or most of the people in a group
This is well spotted and understood, but its equivalent in my opinion to people complaining about accidental misuse of "their, they're and there" in posts, especially when it's in the proper context. Yes its most correct, but that just takes our focus away from the message of the speaker, author, etc.
P.S. - how long did you stop at the last 'its' that should have been an 'it's'?
He grasped what the video was about and offered an opinion on it, didn't he? Therefore, I assume he knows what I am talking about. Besides, it was the video presenter, not the OP who said "current flow"
It is like I said, it is a slang term. Slang is usually not precisely descriptive and should not be used to teach beginners. All of the members in this forum know something about electronics, or are interested. Therefore, I would not call the members laypeople.
That definition by Merriam is vague, because "electricity" means just about everything electrical. Defining current as the flow of charge or charge flow is precise and descriptive.
I think we can disregard the other nonelectrical definitions for this discussion.
Au contraire, using the wrong word or misleading slang interrupts the thought and derails the focus.
A mistake in grammar is not the same as a wrong definition caused by slang usage.
Ratch
Perhaps. But the OP does ask for our opinions on the matter as he states he is unsure after watching it. (states "I think").
I disagree. A layperson is someone without professional or specialized knowledge in a particular subject.There are many members here who are very highly educated in electronics, some may have doctoral degrees. In contrast many other members come here to ask question's about more simplistic matters such as how to power a LED. I would consider them as well as myself as laypeople.
Splitting hairs. According to the textbook I consulted, "V=IR is sometimes called Ohm's Law, but only when referring to materials or devices for which R is a constant independent of voltage - i.e. metal conductors.
How often does a technician apply Ohm's Law to nonohmic materials during troubleshooting?
HellasTechn
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That is true chopnhack. I neither support nor weaken what is stated in the video.
The only thing that i say i agree with is that maybe it would be better to use Ω and A instead of R and I. But again it is no big deal.
About my comment on part of your post i just wanted to point out that in my personal opinion it is better to use the term current flow or charge flow rahter that current being present or existant thats all.
The only thing that i say i agree with is that maybe it would be better to use Ω and A instead of R and I. But again it is no big deal.
About my comment on part of your post i just wanted to point out that in my personal opinion it is better to use the term current flow or charge flow rahter that current being present or existant thats all.
Question asked, question answered.
Just because some of us don't do electronics for a living doesn't make us laypeople. The amount of specialized knowledge we possess elevates us above the person who is clueless as to how electronics work. You can find people of all degrees of electrical knowledge in this forum, but most of them have a basic knowledge of electronics.
Splitting hairs? The formula is a definition, and the law is a property of a material. That should be quite a distinction in anyone's opinion. Get a new textbook.
He doesn't. A tech is usually not concerned with the property of a material during troubleshooting.
Ratch
As I stated before, since charge flow means current, why add an extra word onto current to make it into charge flow flow?
Ratch
Not what I said, reread the definition I provided.
The splitting hairs comment was aimed at your comment of "Ohm's law in not V=IR and all its variations." The textbook is new and quite clear as I quoted previously.
My point exactly. A technician does not need the same level of minutiae in his study of the matter to service the equipment he will be working on versus someone doing research in the field of electronics. And this is what the presenter was doing as I remarked in post #5.
Since the OP got what he needed, I don't feel our continued discourse over lingual technicalities is adding anything of value.
Cheers!
HellasTechn
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Hmm, what do you all think about what he says in the first minutes of the video about when should the math be taught to the students ?
Martaine2005
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I kind of agree with him......Because I have difficulties even with basic math...But.....
If I hadn't of "bunked" school lessons, I might not suffer with mathematiphobia!!
18 and 19 year olds should already be doing advanced math, so simple series and parallel resistor calculations 'shouldn't be a problem.
His wording is incorrect in my opinion too. He shouldn't be teaching math. That's the math teachers job! Then he can just apply the equations, knowing the students understand the math!!.
I wish I had listened at school now!!
Bit of a double edged sword really!!
Martin
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