Physics Online Reveals Paper 3 Secrets

[@zhelyo_physics]

What websites do you use for Physics? Head over to Lewis' channel to check out another video we did! kzbin.info/www/bejne/l5bGqoB4i8qphJosi=9kE1VZ0XOPyl1LbL

[@annabelross5885]

HOW DID I NOT KNOW THIS COLLAB EXISTS AND I FIND IT THE DAY BEFORE P3

[@zhelyo_physics]

Hope this is useful! Still better than day after : ) Good luck on Monday!!

[@abrahamtharakan]

same here lol

[@user-wv6xj9wn5b]

I did not know this collab exists and I find it the day of p3

[@BlazingFury]

​@@user-wv6xj9wn5b😃same boat

[@abrahamblackman8424]

@@user-wv6xj9wn5bthat makes 2 of us, good luck

[@Dan-pi6dx]

high level collab

[@zhelyo_physics]

Thanks Dan! Hope you are well!

[@laeyak6550]

Love this collab! This video is gonna be very useful, ive got a paper 3 exam at the end of this week.

[@zhelyo_physics]

thank you so much!

[@calisthenicsultan]

Yeah Im finished ive never done a single paper 3 past paper in my life and got 1 DAY LEFT

[@zhelyo_physics]

my best advice will be to do as many as possible this evening and tomorrow and analyse them carefully. Good luck, you can do it!!!

[@The_one_that_got_away]

How tf😭😭😭 what were youre grades

[@calisthenicsultan]

@@The_one_that_got_away ABC with C in physics ouch

[@kattarallapinky9206]

it was so funny when u said "if you find your self writing 9.81 make sure your on earth"

[@mubaris.s]

the most wanted collab of century 👌

[@zhelyo_physics]

Haha thanks a lot for the comment!!

[@mubaris.s]

@@zhelyo_physicslove you teacher

[@nittycityminecraftmultipla9383]

We need more of this collab

[@lw6421]

crossover of the century !!

[@zhelyo_physics]

Indeed! 😂

[@HH1-n1x]

What a collab 👏

[@zhelyo_physics]

Thank you so much! Glad you enjoyed it.

[@yashnarain1072]

For question 2 a) (around the 17:28 mark ), can you not use a data logger and light gate?

[@zhelyo_physics]

for a time period nope, as the gate measures the amount of time spent between the light gate terminals. What is also accepted is using filming using phone with a timer in sight. (mentioned in the examiner's report).

[@SamuelHuggins-c7k]

@@zhelyo_physics A light gate and a data logger can measure the time interval between interceptions of one light gate no? The time period is 2 times the logged value?

[@tosinpedro4783]

The duo I never knew I needed

[@finite1731]

Hi ZPhysics, Do you have any tips on physics & maths undergrad interviews? Specifically I'm looking at Manchester's maths and physics course.

[@zhelyo_physics]

that's funny, that's the exact course I did at Manchester! I think for interviews I would prepare in two parts: research why you have chosen that particular university (have a browse through their websites, they have amazing research groups there) and 2nd for the problems: keep calm, show your working and remember that the problem solving is in a way a conversation. Good luck, it's a great course!

[@finite1731]

​@@zhelyo_physics thanks

[@zhelyo_physics]

Here is a very old video I did on the subject: kzbin.info/www/bejne/d5CoY3yJrLF1bqssi=4AooWaPYKfUph7IB

[@SKPlayz34]

1 hour and half left until p3 , this might be a life saver

[@candys1205]

Elite collab 🙏 hopefully OCR won’t cook me for paper 3

[@zhelyo_physics]

don't worry, you will cook instead!

[@elcolubrid]

im cooked

[@Osamu_Dazaiii]

​@@elcolubrid Sameee!!! 2 days left!!

[@maximusekon146]

Good video, do you have a video on how to prepare on Paper 3 and also which paper was used in this video or were they just random questions

[@zhelyo_physics]

I do have a paper 3 video: kzbin.info/www/bejne/oZbaqKyKm7qWlbcsi=5rxfhjCc8E1Imo60 We have a link to the paper and the question numbers in the video description. Hope this helps!

[@rames108]

Sick collab

[@boyyeah6364]

When calculating the percentage uncertainty, you got a value of 10%. Why did you leave it to 2sf and not 3sf? Would 3sf have gotten the mark?

[@My-fb5td]

yes 10.5% should have been fine aswell.

[@zhelyo_physics]

Agreed

[@azkaazzahraaristiorini8815]

Help me a lot as a teacher. Love from Indonesia 🥰

[@zhelyo_physics]

amazing to hear! Thank you for the comment and all the best!

[@xhibah]

paper 3 is the easiest for my exam board ahah, paper 1 on the other hand… and it’s the first paper i’m sitting 🙃

[@zhelyo_physics]

Which exam board is this? They can vary in difficulty a lot between years too.

[@xhibah]

@@zhelyo_physics ocr b

[@unravel9716]

Okay why do all physics folk have square black framed glasses? 🤓 My teacher's got it too (even the hair damn it)

[@PhysicsOnline]

Just the look!

[@oscarpeters5309]

if paper 3 is the hardest... after paper 2 i'm cooked

[@zhelyo_physics]

Fingers crossed it's easier, good luck revising!

[@dhruvbilurkar6111]

Caan u solve some problems on fluid mechanics so that atleast we get an idea on howw to approach fluid mechanics problems appearingg in exams. Like jee advanced, international physics Olympiad.plz sirr. Btw love your work

[@zhelyo_physics]

Here is a Bernoulli Problem : ) kzbin.info/www/bejne/eZTHioSVaZ2Dbbcsi=4KgvUJdaaMpCIw5B from the JEE/IPhO (appeared in both) Hope this is useful!

[@dhruvbilurkar6111]

@@zhelyo_physics can u try some problems from the book Pathfinder

[@BedlessPro1]

I want to cover all A level physics, As A2 …… with problem solving questions. Where should I start’ I mean topics from this channel to cover everything properly?

[@zhelyo_physics]

I have the perfect playlist for you: kzbin.info/aero/PLSygKZqfTjPC3hJ7nRSnnXTw3tI_o67dR The whole of A Level Physics in about 13 hours. Supplement this with exam questions and papers. Let me know if something doesn't make sense! : )

[@osmansadat9650]

do you recommend the aqa practical physics textbook?

[@zhelyo_physics]

I have not actually used it so hard to give a definite opinion but I do like textbooks : )

[@Thorfinn.05]

Any tips for doing the paper without feeling burnt out by the end of 2 hours and 30 mins. If i start feeling exhausted i would not be able to give my 100% brain power to the very next question.

[@zanexlmao]

this paper is only 70 marks and 1 hour 30 mins so you should be fine hopefully

[@Thorfinn.05]

@@zanexlmao I'm doing edexcel physics

[@zhelyo_physics]

I think practice makes perfect. Do a paper in exam conditions today if you have saved one and see how you feel and any ways to improve. You got this!

[@Thorfinn.05]

@@zhelyo_physics thanks, I have got the timing down to 2 hours and did a practice paper in the morning. I think the only thing I struggle with is choosing a right scale for a graph question. Do you have any videos regarding that ?

[@TheodoreKoripamo]

Crossover of the Century 😂

[@zhelyo_physics]

😂 agreed!

[@FireFN]

1ciii) I don't understand why contact force isn't greater at Probe B then A. Isn't the contact force the force acting on the Probe which is the total force the probe acting on the planet? Centripetal force + the weight should result in a greater contact "resultant force" since the centripetal force is acting in the same direction as weight.(???) (chatgpt even agreed with me which made me even more confused, but thank you for the video and collab ❤)

[@zhelyo_physics]

Unfortunately chatgpt is definitely not a reliable source. In my chatgpt test video it got Kinetic Energy problems very wrong (surprising to be honest). But to answer your question: On the pole: Sum of all forces: W-U-R=0 (1) On the equator: Sum of all forces W-R-U=F (2) where F is the resultant centripetal force, From equation (2) Rearranging for R: R=W-U-F On the pole equation (1) rearranging for R R=W-U On the pole it will be bigger because W-U will be bigger than W-U-F I think Lewis did basically this but taking up to be positive. Intuitively, if you look at the arrows drown in the video: In the first diagram: N needs to be quite big to fully balance the whole length of arrows of U and W, on the equator, it doesn't need to be as big because it doesn't balance the whole of the downwards force but leaves a bit pointing downwards. Hope this helps! I am writing this on my lunch break so please just double check my algebra above : )

[@mooodlemip4779]

Shouldn't Fc have a negative sign? cos its acting in the opposite direction as upthrust and Nb

[@My-fb5td]

nah Fc is just the resultant, its just there because weight > upthrust and Nb which happens bc B is in circular motion so it must have a net force to the centre, and net force = centripetal force = W - (U + Nb), makes sense?

[@mooodlemip4779]

@@My-fb5td I get you but in this context throughout that whole q physicsonline was resolving upwards - so that all upwards forces (U and Nb/a) were positive and all downwards forces were negative. however when he got to writing the equation for Fc he said that Fc was positive even though Fc is acting downwards, this meant that if you rearranged to get Nb on its own you'd get Nb = Fc + W - U, making it seem as though Nb is bigger than Na (cos we know that Na just equals W - U). this is not correct therefore in this context its important to make sure you are consistently resolving in one direction otherwise you come to the wrong conclusion

[@My-fb5td]

​@@mooodlemip4779 Ah I see, resultant force is in the direction of the dominant force, which would actually mean that Fc is 'negative' bc the dominant force is weight > Nb + U, and if he assigned down as negative, so i'm not sure thats right. It actually works your way aswell, taking down as negative: (U+N) - W = -F, is the same thing as taking up as positive W - (U+N) = F, where W and F have the same signs bc the same direction, ig the convention may be that you always want to resolve the net force in a way where the dominant force is positive bc that way it makes it less confusing, lemme know if this made any sense lol.

[@zaidakasha2]

what are your tips in terms of the order of answering the questions, I try to answer them in order and any that I don't get I move on but I feel like this makes panic and rush the other questions, but If spend too much time on the question I end up wasting time and missing easy marks on other questions

[@zhelyo_physics]

Practice makes perfect, you got this!

[@zhelyo_physics]

Favourite constants? 🤔

[@lolaharwood619]

h=6.62607015x10^-34 is one i committed to memory for some reason, not very helpful though as on the data sheet its only to 4 sf!

[@teacupcakes2739]

Molar gas constants k = 1.38 x 10^-11 R= 8.31 is there a reason why 1.38 and 8.31 are backwards i find it intriguing. But my other favourite pair is planks and hubbles. They are both world defining constants which makes me wonder why they exists.

[@TaseenTayhan-et3ig]

Hi!

[@zhelyo_physics]

Hello! : )

[@andrewt4420]

collab we didn't know we needed

[@zhelyo_physics]

thanks for the comment! We have another video coming out tomorrow on Physics Online : )

[@kushagrasinha4828]

I thought these guys we're the same😮😮

[@petergcda9645]

For probe B: W-N-U = F surely.

[@erdemcelik6692]

Lettssss goooooooooooo

[@God-gi9iu]

🥶