MANY Students Get This Physics Question Wrong

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@zhelyo_physics 6 ай бұрын

So out of curiosity have you come across this type of problem technique in school/college? Did they solve it in a similar way? I hope revising is going well!

@marshallmanz123 6 ай бұрын

Couldn't u have just removed 4.67 from 4.74 to get the potential difference? As current at that point in the top branch would have 4.67*q joules of energy and in the lower branch; 4.74*q joules of energy.

@zhelyo_physics 6 ай бұрын

@@marshallmanz123 essentially this is where Kirchhoff's 2nd Law comes from. Excellent. Sometimes the polarity is important though as you can have multiple resistors in the top and lower branch and you may have to write a longer equation.

@Allinone-nm2jh 6 ай бұрын

Not really , I only find out about these type of questions through your videos .

@sakib7745 6 ай бұрын

Can we say that the potential of the negative terminal of the cell is zero volts?

@Allinone-nm2jh 6 ай бұрын

@@sakib7745 no

@thevinecompany7733 6 ай бұрын

hello sir! i hope you remember me 2 years ago you helped me so much in my A levels and remember I called that you would become famous haha! I come back every year to check how the account is doing I am in second year uni engineering because of you. Keep smashing it with the videos helping out students more than you believe. God bless you man

@zhelyo_physics 6 ай бұрын

Of course I remember! Great to hear from you!! You asked excellent questions and worked very hard, how is engineering going? I hope all is well! It is amazing to get messages like that and they make my day. Hope all is well and that 2nd year goes very well. Good luck!

@theweekndsintern1925 6 ай бұрын

Interesting. My first thought was that it would be 0V since branches in a parallel circuit have the same potential difference. Why is my reasoning incorrect?

@My-fb5td 6 ай бұрын

Because the total voltage is the same, but between those two points the voltage changes as the resistor values are different

@theweekndsintern1925 6 ай бұрын

@@My-fb5td ah okay thanks

@zhelyo_physics 6 ай бұрын

Excellent question and answer! Interestingly actually the condition for balance (V=0) is that the resistors on the left say R1 and R3, and the resistors on the right say, R2 and R4 are in the ratio R1/R3=R2/R4. Any other combination will produce non-zero p.d. Hope this helps!

@theweekndsintern1925 6 ай бұрын

@@zhelyo_physics thanks sir that helped 😁

@ThanaNorman 6 ай бұрын

Awesome! It'd be nice to get a video that goes through common 6 markers and the structure to answer them if possible :)

@zhelyo_physics 6 ай бұрын

kzbin.info/www/bejne/j5TRkKRpaplmqK8si=rTwq1XU2HsfAoXzU I made a video on this some time ago actually : ) Hope this is useful!

@ZainabBaig-lz6hy 6 ай бұрын

I'm confused about why the current across resistors of 7 and 8 resistance would be the same. If there is a potential difference, won't some of the current move downwards leaving the 8 ohm resistor with less current?

@RoofusRoof19 4 ай бұрын

Great video! Straight to the point, perfectly explained.

@zhelyo_physics 4 ай бұрын

thank you for the comment!

@Anime_World1168 5 ай бұрын

sir , i dont understand why u add or subtract emf/voltages in a circuit with multiple sources of emfs , why did u subtract those voltages

@zhelyo_physics 5 ай бұрын

So have a look at the plus and minus signs on each resistor. If you are going in the loop and you go through each resistor + to -, take the voltage to be positive, if you are going - to + in the loop, take the voltage to be negative. Hope this helps!

@lbrandon1227 6 ай бұрын

Thank you I urge you to do more of these❤

@zhelyo_physics 6 ай бұрын

thank you for the comment, will do!

@lbrandon1227 6 ай бұрын

@@zhelyo_physics thank you

@kskeedits 6 ай бұрын

Hi sir, what topics would you say are the most valuable to revise in terms of how often they come up for OCR A physics papers? I fell behind a lot of topics as I couldn't attend classes due to being ill. Thanks in advance :)

@zhelyo_physics 6 ай бұрын

So unfortunately it's completely impossible to predict which topics are more likely to appear, there is still time to go over the entire specification. This playlist covers the whole content: kzbin.info/aero/PLSygKZqfTjPC3hJ7nRSnnXTw3tI_o67dR&si=WdJZjoI-aNV3Ofor Hope this helps!

@justblitz1566 6 ай бұрын

Sir I just wanted to say thank you so much for the help in these past few weeks. There was a video you had made about finding the voltage in a circuit using lost voltage that really helped me understand the concept, which I was able to apply in a recent test. These videos that you post about the exam tips and questions that are difficult to score are super helpful and I hope you will continue to post more like this. Thank you once again, may god bless you!

@zhelyo_physics 6 ай бұрын

wow amazing to hear! Thank you so much for your comment! Very much appreciated!

@bossgamer9411 6 ай бұрын

wait so you can do kirchoff's 2nd even through a loop where current won't flow? As in, current won't flow through an ideal voltmeter but we can still consider that loop?

@zhelyo_physics 6 ай бұрын

abolutely, we calculate the difference in electrical potential between any two points

@Syrupsandwiches69 3 ай бұрын

Goated pfp

@jamieasypeasywdasqeezy3728 6 ай бұрын

Why doesn’t the volt meter take a reading from the other resistors surely you would need to subtract the difference from the parallel meters on the left

@sharin6an73 6 ай бұрын

If you do that you'd still get +0.07V so it shouldn't matter

@qarcin12 6 ай бұрын

I think its because the potential diffrence across the 2 resistor branches ought to be the same as the sum of the pds across the first top resistor branch and second bottom resistor branch must equal to 10v (kirchoffs second law) so doesn't matter which branch you choose to look at, I don't think you would subtract however as this - due to what I said previosly- would give you 0v. @zhelyo_physics ?

@zhelyo_physics 6 ай бұрын

so you can apply kirchoff's 2nd law on any closed loop in a circuit. In a complete way actually Kirchhoff's 2nd Law is written as the sum of the all the voltages in a closed loop is 0. You can apply the same rule for the resistors on the left and you would still get the same answer (keep in mind you'd be going through the voltmeter negative to positive so you'd get -(-0.07 V)

@JingleBets 6 ай бұрын

@@zhelyo_physics @sharin6an73 When taking the difference of the potential differences of the resistors on the right, the exact value is 4 / 57 = 0.07 V but for the ones on the left, the value is 3 / 57 = 0.05 V. Can we take them then to be approximately the same?

@My-fb5td 6 ай бұрын

How do you know which part of the branch gives positive / negative pd?

@zhelyo_physics 6 ай бұрын

Excellent question, so if we do the loop on the left, in the clockwise direction, we will go through the voltmeter negative to positive, so we will end up getting -(-0.07) i.e. +0.07 m . I hope this helps, fantastic question!

@JoshuaAdebayo-ru5up 6 ай бұрын

@@zhelyo_physicswhy would it be -(-0.07)?

@craftmore7815 6 ай бұрын

Why is the emf O not 10? Thanks

@zhelyo_physics 6 ай бұрын

as there is no source emf is in the smaller loop. I hope this helps.

@axviiaxvii5909 5 ай бұрын

Hello sir. I am quite confused as why you are taking away. How is it - to +?

@zhelyo_physics 5 ай бұрын

When going around the loop if the polarity is + to - , add, if it is - to + , take away. Hope this helps!

@2024physicspaper 6 ай бұрын

Hi, I'm a bit confused on how you decided if it is minus or plus?

@alaziziomar_ 6 ай бұрын

conventional current goes from the positive terminal of the battery to the negative. positive is the longer line, negative is the shorter line.

@imageneralphysics 6 ай бұрын

You're right👏

@Xarishher 6 ай бұрын

Why did you not try the usual approach to Circuit Questions which is: (1) Calculate Total Resistance. (2) V = IR for Whole Circuit (3) Calculate I (4) Calculate Voltages of each resistor. (5) Complete the main question asked.

@zhelyo_physics 6 ай бұрын

Interestingly I did essentially this. By finding out the ratio of the voltages having to add up, to the p.d. across this branch, this is essentially equivalent to finding out the current and then finding the p.d. across each resistor. It is much much quicker though at least in my experience. Then I applied Kirchoff's 2nd Law. Hope this helps! Excellent question!

@Xarishher 6 ай бұрын

@@zhelyo_physics let's say you do it my way - how would you calculate the total resistance for that circuit?

@Xarishher 6 ай бұрын

@@zhelyo_physics also a small request - Can you go over some harder lenses questions with this style of video. I would like to see your way of approaching such questions.

@ManishSahu-t4g 6 ай бұрын

hey, can you make a video regarding different coordinate systems sand how is stuff like motion and all described in them, would be a great help. By the way nice video

@zhelyo_physics 6 ай бұрын

excellent idea! I touched upon some of this in this video: kzbin.info/www/bejne/i2nFqWprrMhlkNE but I think it deserves its own video! thanks for the idea!

@vedantnagmoti7340 6 ай бұрын

Sir where are you from

@zhelyo_physics 6 ай бұрын

I am from Bulgaria but I have been living and teaching in the UK for a long time

@FunnyAstronaut-bg8qd 6 ай бұрын

How much shold one spend for physic if he had to reach ipho level in 1 year daily

@zhelyo_physics 6 ай бұрын

Very difficult to say, best advice I can give is solve as many problems as possible, enjoy the process and learn some great physics! You can only win with that.