Momentum in 2D - A Level Physics

Рет қаралды 164,558

DrPhysicsA

11 жыл бұрын

A explanation of how to calculate momentum in 2 dimensions.

Пікірлер: 189

@Victoria-rx3gu 7 жыл бұрын

In Korean, saying Soh Cah Toa sounds like "A cow is vomiting", so it's quite easy and amusing to remember the trig functions. xD

@collinschiagozie7367 4 жыл бұрын

😂😂

@Sasukej2004 4 жыл бұрын

In english it sounds like succ a toe

@DrPhysicsA 11 жыл бұрын

Thanks for your very kind comments. My videos are intended to cover the ground for AS and A2 level of the Edexcel, AQA and OCR syllabus. Alas, I wasn't able to distinguish between the material needed for AS and that needed for A2. However, all the AS material ought to be there.

@msimelelogcayiya8709 10 жыл бұрын

your students should be proud to have a brilliant lecture like you .you know what you are doing, you derseve a unique noble price

@The112Windows 9 жыл бұрын

*Nobel prize

@hamzadanial5892 5 жыл бұрын

@@The112Windows everything comes at a price.

@eddymonmon6275 4 жыл бұрын

This guy is a living legend You make the most difficult and confusing chapters in Physics so easy to learn, it's honestly a talent

@Karbonics 8 жыл бұрын

you have balls going in and balls going out. - DrPhysicsA

@philipchristiansen1495 7 жыл бұрын

Balls come in, balls come out. You can't explain that.

@inthebackwiththerabbish 5 жыл бұрын

You’ve got balls coming in, and balls going out - (DrPhysicsA) Correctly corrected by me, pointing out the mistake of Karbonics

@AlchemistOfNirnroot 9 жыл бұрын

Your videos are really helpful for Mechanics in Mathematics as well :P

@DrPhysicsA 9 жыл бұрын

+AlchemistOfNirnroot Thanks. Glad they are of help.

@DrPhysicsA 10 жыл бұрын

Where the collision is elastic that means that both momentum and kinetic energy are conserved.

@madinsomaniac 9 жыл бұрын

Wow, this tutorial really is spoon feeding me just magnificently.

@user-nv7uq3zj5e 5 жыл бұрын

Thank you very much! You're the best physics course videos out there, you are clear with your explanations, don't go off tangent and actually tell us _how_ something works so we can have a chance at understanding the logic behind something, instead of just "here's the name for this new concept, now use it". Would gladly donate for your work!

@sillysad3198 8 жыл бұрын

i recommended this course to all my friends who have school-age kids. Bravo!

@DrPhysicsA 8 жыл бұрын

+Silly Sad Many thanks.

@doseoffaiyaz 7 ай бұрын

It took a while to find the correct video on KZfaq out of all the mess and I have to say this is it! THANK YOU!

@bajiyaa7955 6 жыл бұрын

I was absent for the first 3 days and i missed out on this in class so i owe you m8😁

@DrPhysicsA 11 жыл бұрын

Just to be clear, the A level videos are in the playlist on A level physics. There are other playlists which are for higher level (usually degree).

@soujanyanamburi3153 7 жыл бұрын

your videos are great. i can understand this easily!! tq so much. i recommended this course to all my friends . my exams also went well...tq!

@ssj4dragonfist 10 жыл бұрын

Found this while doing a last minute cram session before my exam, helped a lot. Thanks!

@pranisha6777 7 жыл бұрын

omg your videos are soooooo helpful!! i love all of them.....Thank you so much for making them.

@TKMusiconline 11 жыл бұрын

It is by far one of the best explanation of momentum in 2D. Thanks!

@attamahcelestine4263 9 жыл бұрын

This tutorial is well thought and presented.

@AnthonyLevine007 10 жыл бұрын

Excellent explanation. Thank you for taking the time to make this video.

@psychodonkey121 11 жыл бұрын

I never did physics at A level because i wasn't interested enough at the time, but here I am learning it now, so thank you very much for making it more compelling and understandable.

@leehauyuan 11 жыл бұрын

OMG!! I requested for this video in circular motions and I never thought that you would really make it!! THank you so much!!

@Egonkiller 11 жыл бұрын

I love this channel, so glad I discovered it, is a great complement for my studies!

@moyrml 11 жыл бұрын

soh cah toa is the funniest thing ive seen since the right hand rule, when i lifted my eyes off a test in magnetism and saw the whole class starring into their hands and making different shapes with it. once again, great video, thank you very much!

@itriied5027 3 жыл бұрын

Thank you so much for explaining the trig SOH CAH TOA part. That helped so much.

@ArunieShyama 10 жыл бұрын

great explanation! Thank you very much :))

@cjp21211 8 жыл бұрын

ive been with khanacademy for awhile now but you make it even easier. you dont go off topic and you dont leave us wondering why something works the way it does. and you dont spend too much time explaining something. thanks please continue videos for as long as possible you help a lot of people

@xxHockeyMonkey92xx 7 жыл бұрын

i agree. although i respect khan academy, i'm never able to learn from his videos. it seems like he stumbles and stutters a lot, and i just have a hard time looking at his harsh graphical aids.

@HIJT2FAUTIKA 7 жыл бұрын

cjp21211 I think he's helpful for math but not chemistry & physics

@satyajeetpatil8177 7 жыл бұрын

He's helpful for Chemistry but there is Matt Anderson and this guy who's made physics easier

@kylemankie 8 жыл бұрын

so,if we given that the collision is elastic ,do we take the velocities as they are or do we have to resolve their components before we use kinetic energy formula ?

@FarhanaAdatia1 10 жыл бұрын

A big thank you from a student in Canada! :)

@narutosasukesakur100 10 жыл бұрын

Keep it up sir! I really love ur video!

@archanachaojiMayrakinani 8 жыл бұрын

awesome vry hlpfullll

@suzannemarsay454 10 жыл бұрын

great explanation, thank you very much!

@roflkunt 11 жыл бұрын

You are a great teacher. It is actually easy to understand now.

@arillashsaravanan9216 6 жыл бұрын

Bro this video is amazing dude. I now understand it, for real thank you very much man.

@DrPhysicsA 11 жыл бұрын

Indeed. I am no snooker player but I understand that if the cue ball is aimed other than at the centre of the other ball (ie slightly to the side) then the effect I have drawn would arise.

@DrPhysicsA 10 жыл бұрын

II am not socially aware of the syllabus for me to give you any meaningful advice. I try to cover material for a range of different exam boards. I hope that my videos would be helpful in final revision and I wish you all the best in your exams.

@DrPhysicsA 11 жыл бұрын

Congratulations. Well done. Go for it.

@sinarezvani7638 6 жыл бұрын

At 4:47 when he writes the incorrect equation, is that just an improper way to write the equation, or even if you plug the numbers in it wouldn’t work?

@user-mx7ns9vg5q 8 жыл бұрын

Intuitively, in the first example, why there's an angle between the two particles while the first particle travels straight to the second particle that is static. Isn't the consequence of the collision is also straight? Or it's an 'assumption' to have this consequence that there's an angle between the particles?

@dhidhi1000 11 жыл бұрын

Im loving your videos!

@yugsth2236 8 жыл бұрын

Where does the formula for momentum p=mv come from? Is there any derivation or logic to prove this relation? And what is the physical meaning of momentum?

@popcornamv3441 7 жыл бұрын

Thanks a lot, this helped me a freaking lot. i have my exams tom and this I was confused with but now i understand this ! thanx for posting this , u saved my ass

@DrPhysicsA 7 жыл бұрын

I hope the exam goes/went well.

@DrPhysicsA 11 жыл бұрын

The basic answer is that you must have the enough energy in the form of kinetic energy in a collision between two particles to account for at least the rest of mass energy of the created particles. Any surplus kinetic energy of the incoming particles will contribute to the kinetic energy of the creative particles. Much will depend on whether the incoming particles annihilate or whether there is simply additional particle creation.

@jinirtinir2582 7 жыл бұрын

simply the best :)

@alimasajwani8438 8 жыл бұрын

This is perfect. Thank you, sir.

@DrPhysicsA 11 жыл бұрын

Its a combination of AS and A2 covering the syllabus of Edexcel, AQA and OCR with some CIE as well.

@geoffphillips8183 5 жыл бұрын

excellent explanation! Thanks

@ayushmanthapa_onion 8 жыл бұрын

Even if i have much to learn for my exams, i can keep my cool because i know your videos will help :D

@DrPhysicsA 11 жыл бұрын

I realise the formulae look pretty horrid. But as I tried to explain in the video, in an exam you would usually be given information about several of the unknowns and you would be asked to calculate the remaining unknown.

@sijanshrestha1192 10 жыл бұрын

Thank u sir alot. You helped me to understand the chapter which i never understood in my class.

@generalgrievous5483 7 жыл бұрын

I knew this isn't included in the a level syllabus, but needed help for the SAT II, does any of your videos cover the topic "angular momentum" ?

@DrPhysicsA 11 жыл бұрын

The point is that two particles travelling in opposite directions can, in something like the large hadron collider, each be travelling at a speed very close to c. This makes the energy of the collision very high and much higher than can be obtained by moving particles hitting a stationary target.

@MrGcoffey 11 жыл бұрын

I think I have just figured out my own question. Is it because of the change from cos to sine? If you were to use the angle between the direction of the ball with respect to the y-axis would the equations be x=V2cosA and y=V2cos(90-A)? Which would be slightly more work and therefore pointless? So it is easier to work out y=V2sinA over y=V2cos(90-A). Am I making any sense at all?

@wintanawelday3228 9 жыл бұрын

Great Video!

@RussellMaguire 11 жыл бұрын

Would it not make more sense to label momentum before in terms of mu and momentum after as mv

@TheMoo1231 11 жыл бұрын

Thanks to your videos I managed to get an A in AS physics :P now im going to do the same for A2 :)

@CrestinaBerzentho 11 жыл бұрын

My question is that when Considering particle collisions how does the Energy Needed to create new particles relate to the KE, for example a particle Aimed at a target, and a particle Colliding with with another particle moving in the opposite direction.

@mahmoudm451 8 жыл бұрын

Thanks! I understood everything! :)

@DrPhysicsA 11 жыл бұрын

Well in practice very few elastic collisions take place because this suggests that kinetic energy is completely conserved, whereas any kind of collision is likely to give rise to sound, heat, light energy. But you can have elastic collisions at particle physics level.

@dhiegobersan2504 10 жыл бұрын

What if the collision is elastic and its given the elastic force of the bodies. How to calculate their final velocity?

@DrPhysicsA 11 жыл бұрын

You are welcome. Hope it helps.

@vedantchimmalgi463 4 жыл бұрын

before watching the video= "no idea what this topic is" after watching the video"= solving the questions with him without mistakes

@PratyashaMohanty-iu9gw 3 ай бұрын

can these vids be used for OCR ?

@samran4 3 жыл бұрын

you deserve wayyyy moreeeee subscribers.

@MrGcoffey 11 жыл бұрын

Hi, this may be a silly question but I am confused as to why the angles for the direction of the "ball" with respect to the x-axis and then with the same ball with respect to the y-axis are the same. For example, in the simplified example at 9:13, why is x=V2cosA and y=V2cosA. Why is it not x=V2cosA and y=V2sin(90-A) as (90-A) would be the angle from your drawn line to the y-axis. Hope this makes sense.

@turicaederynmab5343 11 жыл бұрын

I recommend taking a look into Feynmann diagrams and the equation 'E=MC2' which covers the behaviour of young sub-atomic particles such as when particles decay more partcles arrive and how energy and particle matter can interact relative too motion (Usually C)

@DrPhysicsA 11 жыл бұрын

How kind. Thanks.

@ZAVELLI 7 жыл бұрын

give this man a nobel peace prize for his contribution to A level physics !!! . by the way sir Can you show us how to solve the unknowns using simulataneous equations

@omsushantkarki 9 жыл бұрын

yo doc .. why is the M1V1sin(gamma) negative at the last part.. shouldn't you put a modulus in the left hand side of the y component ( again I'm talking about the last example) ... so that the one having the smaller magnitude will be subtracted from the one having the bigger magnitude ????

@DrPhysicsA 9 жыл бұрын

+sushant karki Its really a question of sign convention. You can use any convention as long as you are consistent.

@alieucoker7853 5 жыл бұрын

best lecture on 2D Momentum

@rainingbeat 10 жыл бұрын

Hello! Great video, but I wanted to ask when you're calculating the momentum of the y-dimension, isn't the negative direction already inside the velocity, rather than out of it? I thought that the formula could be always written with pluses, and you took care of the minuses when calculating the velocity. Thank you so much for sharing your wealth of knowledge!

@foxwithaplan858 4 жыл бұрын

Correct, you can write it with pluses if you are consistent with your angles. In the video alpha (~40°) and beta (~30°) are measured to the same axis but in different directions. This error is undone by later manually adding or subtracting by hand. If you measure all angles in the same direction (e.g. alpha=40° and beta=-30° or 330°), you convey the direction-information to the formula where sin(beta) now has the same magnitude but negative sign. Hence you can just add all terms, no manual decisions necessary.

@jirilgonxi2579 4 жыл бұрын

This was amazing

@juniyasteffi3790 3 жыл бұрын

i just can't without commenting on this blessed video u see i 'm watching this video in 2020 (i mean after sooo many yrs) and still it's effective i srsly can't understand a shit when our physics sir teaches and this video............just saved my ASS!!!!!!!

@bakshiparv 7 жыл бұрын

Who else thinks this man deserves money for his wonderful content ?

@007myzorro 6 жыл бұрын

parv bakshi You are right, he deserves a lot of money for sure !!very clear and cut expained. all logic !

@007myzorro 6 жыл бұрын

parv bakshi Never seen such a good teacher. He teached in kings college in the past so no wonder for his competence level and such an entousiasm !! let s make a collect for him . He deserves that largely !!

@Grace-vd5tb 11 жыл бұрын

Hello! Can I know if this is for H3 or H2 or H1 a level physics syllabus

@chriscross1152 11 жыл бұрын

Hello Doc. Another efficient video on a classical subject. So thanks again ! There is anyway something to be precised. In your first example (one snnoker ball at velocity v hitting another ball at rest), if the hitting ball is hitting the rest ball just in its center, the two balls will go in the same direction (alpha=beta=0). To get the situation you described in the scheme, the hitting ball should hit the second ball at the different point than the center of its section. Do you agree ?

@sambiker4478 11 жыл бұрын

So. Four post-impact unknowns and (for elastic collisions) three equations. How would we predict the complete post-impact calculation? That is, to calculate all four unknowns.

@edemahlidza743 9 жыл бұрын

now that is lovely. thank you very much

@arushibhargava 11 жыл бұрын

had to create a Google account and sign in just to tell you how amazing you were.

@rishabhvishwakarma1608 11 жыл бұрын

Can you give some examples of elastic collision

@AquaBlade01 11 жыл бұрын

Okay, I'm kinda confused, once we've got x= m1v1cosA + m2v2cosB=m1v3cosY+m2v2cos(delta) and y= -m1v1sinA + m2v2sinB = m1v3sinY- m2v4sin(delta), Do we have to do a Simultaneous equation??? Or do we just write down in the exam X= this and Y=that? /: Cause now I know the formula, but not what to do with it /: Can anyone help??? thanks!:)

@hrperformance 3 жыл бұрын

this guy is awesome at teaching

@hariszahid9607 7 жыл бұрын

bro keep on making such helpful video's

@AquaBlade01 11 жыл бұрын

I get the idea about it now!:D Thanks Dr :) Thanks a bunch for theses videos btw, inshallah because of these I'll get a B in Physics!:D

@sanjeev.rao3791 11 жыл бұрын

I love you sir. I'm going to do my AS level exams this May/June and I'm currently studying the A level portions in my school, and this has helped me a lot. However, do you have any videos that are specifically meant for the AS level curriculum?

@s.usmanali3543 7 жыл бұрын

hi Sir i really like this description.

@sadimannan7248 10 жыл бұрын

Hi, I was wondering how you managed to get such a clear video of 21 minutes into a file of only 55mb. Can you tell me what camera and software you use to make your videos and perhaps what resolution and frame rates you use. It would be really useful. Thanks

@DrPhysicsA 10 жыл бұрын

I do not have any particular special equipment. I use a Panasonic SD RS 26 camera and I mix down the video on iMovie on a MacBook.

@DrPhysicsA 11 жыл бұрын

Very kind of you to say so.

@Kurzux 4 жыл бұрын

19:11 If I saw those two formulas in GCSE, I would have straight up gotten a heart attack. It's mad to think how much your knowledge can improve in less than a year.

@alexandrucoca9770 Жыл бұрын

tigan

@johnbingham6355 5 жыл бұрын

Concerning the two balls colliding along the x axis( Horizontally) I would have thought that the outcome would be horizontal: Or in snooker jargon the fist ball would "follow through"so that both would end up in the pocket.

@hammadhussain4957 3 жыл бұрын

sir do your lectures cover Physics AS 9702 CAIE syllabus??

@CivilBasedGod 11 жыл бұрын

thanks so much!

@DrPhysicsA 11 жыл бұрын

At 9:13 the video says x=V2cosA and y=V2sinA. Sin(90-A) = CosA I think you answered your question in your subsequent comment below.

@lrobertiii 8 жыл бұрын

I have a question, I am an aspiring physicist and I wish to learn everything I can about all branches of physics and I want to know, in what is the proper order to learn in your video playlists, from start to finish? Like which ones should I begin with and which ones should I conclude? I imagine I should start with classical mechanics and the final should be nuclear physics but what about between that? Thank you professor.

@DrPhysicsA 8 жыл бұрын

+lrobertiii My videos are organised into playlists and in each playlists the videos are in the order I recommend for watching. As to the order of playlists, I would start with GCSE, then A Level, then any order you like for the uni level material except I would watch the Quantum Mechanics playlist before you watch the particle physics playlist.

@Tordoff19 7 жыл бұрын

u are my hero

@zameerosman5886 10 жыл бұрын

Sir, You are amazing. Anyways I am retaking my AS level physics exam in a week. Paper 2 is in 8th November. I am retaking as I got this horrendous 53% grade this May. For paper 1and2 I am thinking that i would go through your videos of the chapters included in AS and your videos of exam questions and then solve recent papers 2010-2012 which includes 18 papers for practice. Is this enough to aim for an 'A'? Or do i need further knowledge. If so sir, then please advise me what i should do next.

@xerp7626 4 жыл бұрын

thank you so muchh

@artemisangelique 9 жыл бұрын

i notice that you dont have a video for SI base unit and vectors. i know its a really basic part of physics but i still wish there's a video on it. physics have never been my strong point so every little bit counts i guess?

@AlexandrBorschchev 2 жыл бұрын

why is it conserved? can someone explain

@mahadow1 7 жыл бұрын

Thanks indeed 👍🏻👍🏻

@oshanbudathoki1159 11 жыл бұрын

sir,thank u very much for these videos,it helped a lot,but i wanna say that plz add videos for experimental analysis of A-level physics.i m quite weak in experimental co-ordinations.