Kirchhoff's Laws - A-level Physics
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- Опубліковано 3 сер 2024
- scienceshorts.net
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00:00 Kirchhoff's 1st & 2nd laws
02:11 2nd law worked example -
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How the hell is a 7 minute video more informative than 4 days of studying?
😏
This is the actual truth
IKR
Exactly asking the same to myself, 7mins over 2hrs of lecture, short, informative concise: thank you!
sometimes i think why do i go into my a level lessons when i have this guy? im deaddd. But thank you so much, electricity is (was) so hard for me and my teacher didnt explain it well at all but now I can answer questions well and get full marks! Tyyyyy
I feel your pain, honestly. So much better explained than in class
I actually always think the same thing!! I learn way more with him! Pls come to The Latymer School in North London and be my teacher😢😂. Mine is awful compared to you…
Actually I watched your first video on Kirchhoff (I refuse to pronounce it ‘keerkoff’) and it taught me a lot more than the multiple lessons at school. This video was great too though!
If that aint fax
Why would you pronounce it Keerkoff anyway ? :D He was german so it’s more like kirshoff or keershoff depending on your dialect.
@@teinili ch is a harch c in german, sch is sh
.You have explained it very well by covering all from simple to complex on electricity. This video was so helpful to turn my negative idea that electricity is difficult to positive.THANKS A LOT SIR.
With a whole bunch of videos about kirchoff rules, the only video i understood to the deep. Thanks a lot
Yaa
Yea men
H
Much better explanation than before, thank you.
The number of dislikes disagrees! 😥
@@ScienceShorts 79 haters behind 79 failed attempts to make better video on this topic.
@@ScienceShorts what do you mean, this video is perfect it literally has no dislikes, I can't see any
This was so easy to understand. Thank you so much!
Your videos are such a great refresher - they remind of what I’ve learnt and then teach me extra details that my teacher forgets
I am going to give my CIE exam tomorrow pray all goes well.
0:53 that is so relatable. I'm always stuck on every circuit when it comes to solving them :(
I'm doing this course where we're learning Op-Amps which seems even harder.
Thanks for the tutorial! I wish most professors I had and videos I found online were teaching the way you do! It's the right amount of detail with the right pacing I was looking for.
We can't thank you enough for all your help! Liked and Subscribed!
my teacher took 80 mins, this dude here 7min.
You've explained better than all my teachers!
Very helpful, thank you!
So informative and very helpful especially for mocks tomorrow
This explanation has defnitely saved me one hell of a headache.
Much more helpful than the previous video. Thanks a lot ♥️
Another great video, please keep up the good work for the sake of me and my friends' a levels
Thanks for the great explanation
Thank you very much you made this way simpler than my physics teacher tried to
EXCELLENT MY DOUBT IS CLEARED
Really helpful video Godspeed
I understood the theory very well and the example also gave me a better understanding. can we have another video with more of these examples please.
Always appreciated and great video! Could you manage to do a video on Viscosity (AS) if you can manage? Thanks a million!
This channel is great
from around 6:35 your statement is wrong , pd across that resistor would actually increase, still good video none the less
Great video
Amazing video
What if we didn`t have the 10 ohm resistor? In one loop it would look like the voltage across the 30 ohm resistor is 10 V and in the other loop it would look like the voltage across the 30 ohm resistor is 12 V
Thank you so much 😭
where can I see the calculation example where you add the extra 10 ohm resistor on the left side?
I have a problem similar to that so I'd like to know how the calculation look like and how to get the power of both batteries.
I'm still learning, but is it possible to say that the the capacitor and the resistor (both 10V) are also 10V, because for capacitors in parallel or resistors in parallel, the voltage stays the same? Or is that something we could not assume?
damn 3 years and still no response? my fault man wish i knew the answer to help u
@@libaanomer1812all good! I still don’t know 😂
Perfect video
Amazing thnks
How many Sharpies do you have?!?!
Like 20 different colours. £10 on ebay. Bargain.
@@ScienceShorts i can smell the sharpies
can you add the emfs to get the total voltage across the curcuit? 4:41
This guy is the real goat
Great video! Thank you ☺️
Hello, thank you! Also could you please explain why it doesn't work at 6:32?
7:05 At the end with the 3rd resistor I get this with a circuit simulator:
V1= 571.43mV, V2= -9.43V, V3= -2.57V
The original values were:
V2= -10V , V3= -2V
I was able to figure out the original values, but I am flummoxed at the moment with problem including the 3rd resistor...
Here's my solution for the original problem:
5:26
/---------V₂-------------\
i₁ -/- i₂ \
___→______a__←__▭________ ....\
|--Vᐩ₁₀ | \ R₂ | \
⨪±10v i₃↓ -\- | ----\-Vᐩ₁₂
|--V⁻₁₀ R₃ [] V₃=Vb-Va ⨪±12v
| | -/- | -----V⁻₁₂
|__←i'₁ ___b/______________/
Vb=V⁻₁₂ - V⁻₁₀
Have:
i₁=i₃-i₂ (or later at 6:08 , i₁=V₁/R₁ with R₁=10Ω)
i₂=V₂/R₂ with R₂=10Ω
i₃=V₃/R₃ with R₃=30Ω
Also:
10v+ (V⁻₁₀ - Vb) + (Vb - Va) + (Va - Vᐩ₁₀)=0
V₃=Vb - Va
Must have i'₁=i₁ as 10v battery must have charge conserved, with incoming=outgoing.
This means the wire voltage from Vᐩ₁₀ to point "a" is the same as from as "b" to V⁻₁₀,
Therefore: (V⁻₁₀ - Vb) + (Va - Vᐩ₁₀)=0.
=> -10v = Vb - Va = V₃
Similarly,
12v+(V⁻₁₂ - Vb) + (Vb - Va) + (Va - Vᐩ₁₂)=0
But here:
Va - Vᐩ₁₂=V₂=V⁻₂-Vᐩ₂, V₃=Vb - Va= -10v
Also, any bare wire has zero resistance & the potential is the same on either end, so V⁻₁₂=Vb.
Therefore, this is:
12v+ 0v -10v+V₂=0
=> -2v=V₂
Can you go over electromagnetic induction
I have a question: isn't it true that E (EMF) is equal to the voltage drop from loads outside the battery plus the voltage lost within the battery itself? How is it then that the EMF is equal to the p.d across just the outer loads in the circuit?
there is an assumption that internal resistance is negligible.
I have the exact same question
Thank you so much .I'm preparing for end of term tests and my as in exam in January next year .
I'm glad I came across your channel
can someone explain why the total EMF for the loop in the final question is 2V
Does the direction of the loop matter??
Does internal resistence not affect the second law?
Thank you so much! Greetings from a freshman from Indonesia!!
For Kirchoff's second law, what is a pd drop?
Potential drop or voltage drop. From my understanding, it's the voltage that gets used by the passive elements from the voltage source.
Dude!! Now I want the solution to when you added a third resistance T_T I found the voltage drop on the new resistance you added zero T_T Why? What did I do wrong? Or am I right?
Could you go over astrophysics in more detail please
If this is astrophysics, then chain me to the wall cause I ain’t going no further. Lol
Do you have a bunch of these as problems that can be solved? Do you know a place that makes them if you dont? Also, What is PD drop. I am super knew trying to figure this out.
An emf is a pd rise. Pd 'drop' merely describes the opposite. It's just a drop in potential.
@@ScienceShorts thank you so much for your video. I just got into this and your content was pretty easy to understand thank you for the clarification.
@@ScienceShorts Does p.d. stand for potential difference? Sorry, I've never seen that shorthand/abbreviation used before.
@@epochseven4197 it does
Thx.
2:01 why does third one push in the opposite direction?
I believe he has something like
this in the circuit shown:
⨪±
⨪±
∸∓
6:17 looks like a fuse to me
Quality video
With the 2nd law, how can you call it a closed loop when there are other currents entering the system?
Just means complete loop, no breaks.
@@ScienceShorts Oh right ok, thank you very much.
Great video 👍
Hi I really enjoy your videos can you do 2 more electricity videos one on mean drift velocity and one on electron Gun
3:52 not explained why the right hand loop behaves differently to left
The right loop has two resistors so it's not straightforward to calculate their respective voltages. Therefore, solve for the middle resistor's voltage by analyzing the left loop first.
so useful thank you!
How is there there the big blue current loop
How is the current moving against the current direction on the left
With the big loop
The arrow drawn for the loop just shows the net direction of p.d., not the current (supposed to, anyway)
6:48 Why can't you split the 10V emf 3:1?
Because it's not the only emf involved!
I got that....thanks mr....respect you!
Do the word "Volt" take an "s" in english to describe its plural? On my every school book I always read that if a measurement unit is called after a scientist, its name doesn't change between singular and plural.
1 meter and 20 meters exist because isn't existed a mr. Meter, but is an error saying 20 Watts, because Watt is the surname of the inventor of the steam engine. Volt comes from Volta, if a reader doesn't know, and Ampere its trivial. I'm curious because I always read a thing that is never respected by english native speakers acadamics
Interesting point. Yes, you're probably right, but it's something that is widely accepted.
should the loop direction match the assumed current direction?
No - you don't know which way the currents are going, all you can do initially is assume. Then, if you end up with a negative current, you know you were wrong.
@@ScienceShorts Thanks for the answer much appreciated.
Bravo!!!
Why does the 30 ohm resistor only take the 10V cell into account, what about the 12V cell. Please reply this is really bothering me.
Because he analyzed the circuit by breaking down into loops. The example circuit he gave has three loops. One loop on the left, one loop on the right, and one big loop for the entire circuit. That's why you see him covering the right loop with his hand when calculating the voltage for the resistor in the middle.
4:27 is it 2v because 10v + 2v = 12v ???
Yes
Thanks mate!
I love you Bro
What is the "emf"? And what is a "p.d. drop"?
emf means electromotive force but I don't know what pd drop is.
Potential difference drop = voltage drop caused by components of the circuit doing work, which ends up being converted to heat.
What sort of application could this sort of circuit have, in a building for example?
how did you get the 2v?
Which 2v? For the 10 ohm resistor on top or the overall emf for the circuit?
Can you what is meant by "p.d. drop"? I know you mean voltage drop, but what is p.d.?
Same thing!
P.d is potential difference which is the voltage
I wonder if it's a regional thing because I've never heard or seen "p.d. drop" when I was in school. I'm guessing in Britain they use p.d. drop and in the U.S. they use voltage drop (which I'm more familiar with).
very good explanation do you provide a private tutorial?
Where's the 3rd law?
i still dont understand why ontop of the 10 ohms is 2 voltage how did you work that out
12-10
@@ScienceShortsyou can't just take away voltage by resistance
Can someone explain why it's I1+I2=I3 and not I1= I2 + I3
I'm confused, aren't you meant to use simultaneous equations? That's what I learned from your last video on this topic.
If you wanted to solve the last example, you would need to - but that is beyond A-level. All it did was confuse people!
@@ScienceShorts Wait hang on, it's beyond A Level? Haha I've gone and learned how to do all that now
Doesn't hurt! 😂
You might have to use simultaneous equations when it comes to forces, but you won't have to in this situation.
@@ScienceShorts Oh well I didn't think simultaneous equations here were that hard, I found it useful. I guess I know how to calculate current for my own personal knowledge lol
In my school they said its always easier to draw all the loops clockwise, to the same direction.
don't you mean potential drops/potential difference?
why did he ignore the 10 ohm?
Rad video brav
could you tell me where you got that final worked example question from?
what are p.d drops ?
Potential drop
p.d. drop = potential difference drop
Legend
Why have you taken different directions in boths loops
Current flows from positive terminal
Holy, I'm glad this isn't in my spec (AQA)
It is, dude.
@@ScienceShorts Oh dear, throughout the electricity specification, AQA does not mention Kirchhoff at all. However, I did find a little section on the AQA book that looks into Kirchhoff's laws.
@@ScienceShorts,You're right, they don't mention Kirchhoff, but they expect you to just apply his principles
Came here to verify if my vocabulary is enough to learn physics in english, and...no, it is not, I'm already bad at Py on my own language
The real question is how you actually do the last question?🤔🤔
I cheated and used a simulation!
(Answers above)
science shorts is the messiah
i really love you sm xoxoxoxoxoox
I have a test in less than an hour wish me luck boys
Again, I don't know why am here
Still doing GCSE's
You still use the ideas at GCSE, you just don't know the definitions 😊
You know that for a potential divider circuit, all the emf must be 'used up' by the two resistors, so it's shared between them according to their resistances.
@@ScienceShorts k thanks
hamzy g basically all the stuff youve been taught about parallel branches having an equal potential drop is actually just a specific case of kirchoff's voltage law. i think knowing this at gcse would have helped me understand circuit analysis better tbh
@@ubaidshah1910 thanks mate
5:18 You said Ohm's instead of Ampere's
No he didn't...
👍
You confusing me .. i didnt get anything
Where did I lose you?
@@ScienceShorts 3:44 forward ..
You said the direction of the current will be given in any question but in trying to solve a question now with no direction of current flow ..
And how did you get that 9 and 3 taking the right loop *time of video 3:46 ....
Got exams tomorrow cant get it at all
If you are not told, then you can assume the directions, and create an equation using Kirchhoff's 1st law (I1=I2+I3 for example). It doesn't matter in the end, because if you got the direction wrong, you'll just end up with a negative value, which just shows that it's going in the opposite direction to what you assumed.
The second bit: have you seen my potential divider video? If the right loop was an isolated circuit, the total p.d. (12V) would be shared across both resistors relative to the resistances. The ratio of their resistances is 3:1, so the 12V would be shared 3:1 too - that's 9V to 3V.
If you're not getting how the 12V is being split up, it's honestly a bit late to be wrapping your head round problems like this mate - just saying.
its I1=I2+I3
So you're saying I'm wrong?
@@ScienceShorts sir i said if write or ur equation is write because in my book says what I told u
@@ammarjaber7238 im confused, im p sure whatever you put it should be right
@@ScienceShorts no sir you are never wrong
Can you please talk slower and have pauses to allow us to digest the new information. Beginners like me are a bit confused to start with. There is no need to rush through.
So you want *me* to pause, when there's a perfectly good pause button? 🤔
@@ScienceShortsI can slow it down in my yt app. Can't they all do that?
Falsch eig aber egal...
Was?
How?
Warum