Ohm's Law V = I R: GCSE revision

[@onicamary123]

Excellent teaching, far superior to any lecture I had in undergraduate. If only all science teachers were like this, we'd have tons more younger people going into science!

[@DrPhysicsA]

Thank you for your very kind comments.

[@um7er]

True

[@Paulskyler]

OMG you sir deserve a medal. You explained such confusing concepts in an understandable way.

[@enduser8709]

Good stuff, I did this math in electronics (college) with a calculator, You make the topic appear easy, and I do enjoy going over this material again looking the electron(s) in action... plz continue the great work there isn't enough people willing to share knowledge.

[@ahamedakmal7104]

this series of videos has help me build a lot of concepts , thank you sir , btw the videos are so good they are more like lectures than revision

[@owyongcheeseng5926]

you are so much better than my teachers. you break down everything for us to digest slowly and i think thats the best way to teach too! anyways your teaching is awesome!

[@krishnasaraogi5413]

Thank you, you teach very well.better than any teacher ik

[@Mastikator]

Wish I had this when I was 15/16 years old. Great work!

[@njyde]

Thank you for making these incredible videos!

[@junaiddar296]

life saver even in 2017. cheers

[@tristanlee6094]

Absolutely wonderful explanation.

[@heracleum3353]

I have found and am finding these videos very helpful thank you very much for this.

[@agulamhussein]

Hi. Sorry but aren't VI graphs supposed to have current at the y axis and voltage at the x axis? Does this matter at all?

[@DrPhysicsA]

You can draw them either way. But if you put V on the y-axis, then the gradient will be R. if you do it the other way round then the gradient is 1/R.

[@bobsteve7186]

DrPhysicsA if i'm in an exam, and i'm asked to label which way current is flowing on a circuit diagram, do i use an arrow to indicate the direction of convectional current, or an arrow to indicate the actual flow of current? (if they don't specify)

[@DrPhysicsA]

Bob Steve Conventional current (from + to -)

[@robertmoyse]

DrPhysicsA if i were to put - to + would i not gain any marks for this?

[@UnGodlyliFe]

Does that mean gradually the potential difference across a battery decreases over time?

[@yashjagani3914]

hello sir, I'm a 15 year old from India I want to learn physics and I see the GCSE physics most basic and understandable for my lvl ryt now , do you recommend me to watch the GCSE series , I only know certain things about physics , will the GCSE course benefit a new physics learner who is not giving GCSE just wants to learn physics?? pls reply soon

[@DrPhysicsA]

The GCSE playlist is the most basic level on my channel. It is the level taken by students aged 15/16 in the UK so sounds right for you. I suggest you watch the videos in the order they appear in the full playlist. Hope all goes well.

[@robeccacarter8244]

wouldn't the lamp filament graph be decreasing? rather than increasing shouldn't voltage be on the x-axis?

[@kianrokni7547]

Isn't a battery as followed: one long line, a short one, a long one and a short one again? And a cell only a long one and a short one? or am i wrong? @DrPhysicsA

[@spannungsquellestromquelle4572]

thank you your explanation is much better than the explanations of the electrical engineering teachers i have had so far. you reduce the topic so that everyone can solve simple tasks after watching this video and give some real examples for the theory and you do not give in to the temptation of explaining to much and on a harder lvl than needed for a pupil. good job. i have a question on your motivation to produce and upload this videos: why do you do this work?? you dont get money and you probably never will get enough clicks to earn money with your y-tube account.

[@DrPhysicsA]

Thanks. I enjoy doing it.

[@ibraheembaloch9772]

you said that the current flows because of potential difference. in other words a diffusion gradient is established and in diffusion no energy is needed so the emf must be zero but its not. how??? plz answer dr physicsa

[@deadlyxcamperxalvi8747]

Hello dear sir, may I know whether if this whole course is for Edexcel IGCSE students as well? Thank you.

[@DrPhysicsA]

My GCSE (and A Level) revision playlists are intended to cover all the topics in the syllabus of Edexcel, CIE, AQA and OCR. But not all the material is needed for each course.

[@youtubeaddict8039]

I'm sorry to ask such a basic question but If I get a negatively charged polyethene rod , and I put a positively charged rod next to it , will the negative charges move into the positive rod ?

[@fartingchungusbunny432]

Yes,

[@7eyedrabbit]

Thank you for uploading the videos

[@ingmariochen]

Can you upload a video, showing the definition of the microscopical origin of the ohms law. by the way, good videos!!!

[@ananthajitsrikanth6249]

23:40 Why 0.7V?

[@DrPhysicsA]

Ananthajit Srikanth You need a pd across the device to cause electrons/holes to move across the junction. It turns out it’s about 0.7v in many cases. Below that and no current flows thro transistor.

[@ananthajitsrikanth6249]

@@DrPhysicsA Thank you so much.

[@jobgajjala8632]

18:17 he says that when the temperature increases the resistance decreases. But at 20:33 he says that if the temperature increases the resistance will increase too? no hate towards you mans your a great man im probably passing my test tomorrow at school.

[@fartingchungusbunny432]

Basically , due to collisions of electrons with atoms, there will be energy transfer. This will increase the temperature of the wire as energy being transferred to the components is not 100% efficient. So if I have light bulb, the energy will be transferred in such a way that part of it will heat up the wire and part of it will be emitted as light energy. The heating up of the wire makes is atoms vibrate which makes it harder for the electrons to then flow through it

[@momalshaikh8548]

Comment was two years ago lol

[@ibraheembaloch9772]

how does a thermistor work

[@sciencefiction2484]

Beautiful explanation thank you

[@ahmedismail6916]

You rock, sir! I just found out my teacher is an asshole.

[@PaperGlazed]

A video on Resistivity would be a good follow up.

[@DrPhysicsA]

Not sure its needed at this level, but I cover it in more detail in my series of videos for A level physics revision.

[@JSDW1]

THANK YOU

[@dukhteramirulllahkaker6666]

I wish I had it during my o level paper...I would have got an A....

[@ibraheembaloch9772]

what u now got

[@samarthsai9530]

But still why do we follow the convention!?

[@TheTrollingKoala]

@Samarth Sai If you follow the direction the electrons are moving you will get a negative current value. So if draw it the other way it's positive. So I suppose it's easier to think about. Also millions of pages of text would have to be re written which would cost a lot for something that doesn't really change much since the Math still checks out either way.

[@mikeunleashed1]

History, Y u make physics harder 😤