XI_74.Properties of fluids. Pressure Intro.

[@speedovercubing8011]

Who's the most amazing Physics teacher? Toh answer hai Mr.Pradeep Kshetrapal.

[@oldfact5420]

Sath Sath numericals kareate to aur behtar hota

[@priyanksingh9540]

@@oldfact5420 sahi bole

[@AsadKhan-ri8yv]

great sir, I am from Pakistan, but learnt physics from u,

[@AnjaliSharma06]

This is absolute gold dust. Cannot thank you enough sir. You are such a lifesaver.

[@mukaramkhan1051]

unique explanation......carry on such conceptual lectures. It really helpful.....

[@bbrai581]

Kshetrapal sir, you are great teacher. Your lecture is for beginners to targeted level. No need for pre knowledge to understand all the terms. Aapki jaya ho.

[@shwetaupadhyay8947]

Pressure is a scalar quantity. The definition proves that...Force and area both are vector quantity hence while dividing their direction get nullified. I hope I am right..Stress is a Tensor quantity. Please clear this doubt sir🙏(no bad comments plz also, I respect sir dont dare to speak words like sir is right u go n understand from sumwer else..he is a teacher I m a student and I can have doubt and also right to question)

[@1997nitesh]

It is very good lecture adaptable to my comprehension............ Thank you very much sir.....!

[@nitinsharmaa]

concept clearing lectures good job sir

[@balakrisahnanbk3297]

Love your explanation sir......Keep making videos .....

[@durgeshkumar-on5qv]

Your teaching process is very good sir...... &thank u

[@Jerin1080]

its a very good explanation of the following topics

[@yashwantsingh5928]

hey sir! your lectures are really helpful to me. I always watch them once before my school lectures. I have also made another copy specially fr ur lectures..thanx a lot sir!

[@peddirajuradha]

It is good lecture very useful for XI class students

[@ManishSingh-mz1tr]

Thank you sir, This help me alot to understand better about mechanism of fluids..

[@uttamsundarray7353]

Thank you sir ......... it was too helpful during the exam

[@mkarthikraja]

sir if a fluid is kept in a irregular box...in which one side is deeper than the other side...sir is the pressure exerted by fluid on the box will remain same or change due to height..

[@AsadKhan-ri8yv]

thinks for reply sir, , may u live for long time, you are great,

[@parimalpaul8603]

it's good for a healthy beginning of a chapter

[@TheSuman1504]

sir i'm still confused about the quantity of prassure why isn't scaler? and tensor quantity what is it?

[@ashrafmohammed8036]

sir your a great teacher.... I will suggest to my college teacher to watch your lectures....

[@rkguptasmart442]

that sound after na scalar hai na vector hai 😂😂12:42

[@javadvtmra]

What a n a we Som class Yaar?Fabuloas Mind blow in g meim bahu t Sur prize ed ho gayaki majihko bahuth a Saan Se ye Sab Samach meim Aaya

[@parasmahajan09]

If u are defining the units of pressure only after reaching upon P = F/A then on what basis do u first establish the relation P ~ F P ~ 1/A ~ stands for proportionality symbol

[@rishabagrawal5743]

sir can u help me about all the properties of bulk matter... plz tell me which videos i have to watch.. plz sir help me.

[@sunbhai719]

Sir how can stones under the railway track act as spring. Can't sand be used in place of it?

[@achalnarsale6557]

sir you are really great but I don't understand what is tensor?

[@adityayanbhardwaj7131]

Pressure is a kind of stress which act perpendicular to surface of the object and it is a scalar quantity Stress is force per unit area And it is a tensor quantity

[@VarunSharma-xl1we]

Respected Sir, Sir please upload numericals also for elasticity and for gravitation...please sir...

[@rkguptasmart442]

sir u said wrong 36:12 .opp direction.agar fluid force laga ra "ground pe" toh uska components sirf ground ko lagega na

[@atulkr.mishra5733]

sir I love the way u teach... really u explain very good. thanks🙂

[@javadvtmra]

What a n a we Som class Yaar?Fabuloas Mind blow in g meim bahu t Sur prize ed ho gayaki majihko bahuth a Saan Se ye Sab Samach mei M aaya

[@nishantbeniwal9651]

Sir why intermolecular force of attraction in liquid is less

[@yashasvishrivastava7692]

sir I want to know that aap jo 11 - 12 ka course dete hain uski cost kya hai aur usme sirf physics bas ke lectures hote ya phir maths and chemistry ke bhi lectures hote hain aur yadi hote hain toh kaun se teachers ke lecture hain sir please sir reply me and I want your contact no.

[@khuloodidreesali8945]

thank u so much SIR....I will ask u questions whenever I will find difficulty...

[@nityanarang7808]

sir..how can stones act as spring?...can u clarify plz

[@shivangdwivedi8836]

sir pressure is scaler or tensor

[@achalnarsale6557]

sir have an question. how the pressure have all directions . because when we pull any object in particular direction it moves in only one direction

[@chandbasha8684]

you are excellent. i love you sir

[@upendersingh6701]

sir, your teaching style is amazing..........

[@sidharthmehra4710]

Respected sir, Its great pleasure to watch all your videos and had been watching since long time.You made my interest in physics. Sir, here at 0:12:52 you said that pressure is tensor quantity but in ncert and pradeep's its written that it is a scalar quantity . Kindly resolve my problem. Thanks once again for your huge support to all children. Regards Sidharth

[@IR_Mishra]

I have no comments for that excellentttttttttt............................ I became you.🤓than every student like me as i like you guruuuu😏you are god for the average student .

[@sandeepbharti1006]

sir, will density be change if we increase the temperature of fluids?

[@JayPrakash-vt1ri]

Yeah it can change and show different behaviour in liq and gases

[@vaivasvattripathi844]

Sir,how can you say that pressure at the bottom of a conical vessel and a straight tube filled upto same height is same, even when the bottom of conical vessel is experiencing more force due to more mass of liquid filled above it....

[@AnkitGupta-xm3be]

sir why u didnt upload solids and fluids ncert back exercise

[@neerajfauzdar3676]

sir Vo elasticity me work prblm to de hi ni rkhi h....sir vo prblm kha de rkhi h

[@sunilkoparde8852]

Thanks a lot sir... You are really great.......

[@nishantyadav1993]

please tell me the difference between cp and cv in cp-cv=R

[@shivanisharma872]

sir ,please can you make a video only for numerical of properties of bulk matter

[@yashiyadav6734]

sir your lecture is very helpful.Thank you so much sir

[@yashbhardwaj6067]

Sir but in NCERT it is given that Pressure is a positive scalar quantity. But 12:50 you said that it is a TENSOR quantity. Sir what should I write in the test?? Scalar or Tensor??

[@yashbhardwaj6067]

@Aemaye. Thanks!

[@sharadkumar2831]

sir, earth pe har particle ya kisi bhi particle mein mass kyu hota hai?

[@rahulsaini3259]

+Sharad Kumar Everything you see around you is matter. And matter is something that has some mass and occupy some space. Every particle have some mass not just on Earth but on any planet. Though weight will be different depending upon the gravity field of that planet.

[@trishasinghsengar3665]

how come pressure is a tensor quantity? It has magnitude but no direction

[@aashaqhussain6513]

ncert text book writes pressure is a scalar quantity ..explain sir?

[@sujithkumar-ph2pq]

sorry ! where is your tution I want to join

[@satishdeore6946]

Sir but in venturimeter practical the area throat is reduced pressure is also reduced so i am confused please clear this

[@ArvindKumar-dq9vq]

sir why only mass is attractive why cant be repulsive

[@SunainaAgarwal1308]

very nice and helpful lectures

[@sujithkumar-ph2pq]

sir where is tour tution

[@sunday6217]

sir please tell me the youtube channel for chemistry class11...

[@saurabhsinghyadav]

In ncert it is written that pressure is a scalar quantity

[@vaageesha68]

awsome video sir !!!

[@beatneetsmartly...]

Sir iski numerical ka link bhej dijye plzzz

[@RohitSaini-lb2mw]

Osm video sir

[@shivamsingh-fv5uy]

sir which book should I refer for physics in class 12 only for my best in school

[@shivamsingh-fv5uy]

sir I am having s.l. arora

[@pranjalisharma8194]

sir i wouldlike to suggest write point wise and give the time to note down , it would b more helpful

[@hardiknegi4346]

+Pranjali Sharma just pause the video when u have to write something down

[@pranjalisharma8194]

I meant to say you can mention when to note down and time means a liitle sapce of interval

[@pranjalisharma8194]

MOHD MODASSIRUL HAQUE Got it !

[@mahimapanhalkar6637]

simply pause the video while writing dumbhead

[@Saksham.Synghal]

you know you can just pause the damn video

[@arpitasaxena1329]

But in case of pressure exerted by a solid we can have direction as pressure in a solid is always exerted downwards as force is downwards due to gravity....plz help

[@sudeshkhetrapal5517]

dimensional formula of pressure ml-1t-2 so what is role of time in preassure.? formula is f / a? why is time reqd.?

[@aliasgarav9888]

sudesh kshetrapal... pressure is inversely proportional to time square...if 'x' amount of force is applied for a short time the pressure will be more... but if the same force is applied for a long time... the pressure decreases...

[@talhajaved3090]

Sir At 53:40 you Say that Area is same in liquid ! How Area is same when the Heights and Widths are different ?? becoz Area is Length*Width*height *****

[@hardiknegi4346]

+Pradeep Kshetrapal sir, you were talking about the area of cross section? and I had the same query, that area thing.

[@JayanthNarlaJN]

+talha javed I guess its the area on which the pressure is applied...the area of the top and bottom surface of the cylinder (surface S1 and S2)

[@CivilForAll]

sir sin kese lete ha ayr cos khab lete ha

[@dharmveerkularia5990]

helpful video sir thanx

[@vivekkumar-zv2fq]

sir you are great teacher

[@Sunny-nv8pp]

can gravity attract light also..

[@syedafzal9556]

no

[@simardmg]

yes high magnitude of g can as that happen in black hole g of black hole is to much that light cant escape out from it

[@amurukishorekumarreddy1281]

It's just amazing sir

[@akashdeep3958]

sir your explanation is very nice

[@ompatel5462]

sir you told that pressure is neither scalar nor vector. But Google tells its scalar. can I explain me plz

[@ayushjakhmola7881]

Google is wrong then

[@adityayanbhardwaj7131]

Pressure is kind of stress and it is a scalar quantity Because it tell about the effect and gives the value of force it does not depend on direction. Hence it is a scalar quantity. Stress is a force per unit area and it is a tensor quantity

[@shilpimazumdar7276]

Om Patel pressure IS SCALAR QUANTITY

[@adityayanbhardwaj7131]

Shilpi Mazumdar yes

[@sanjayjangir5763]

Yeah sir is right.. There is some logic... U can understand by your sir!!!! Google is also right!!!!

[@Destroyerdhruvrathee]

sir, don't u think pressure is scalar in quantity. why have u added a new concept about tensor if u r saying that pressure is tensor then according to your concept work should be also tensor in quantity cuz w=f.s , it contains two vector quantity. any quantity will be either in scalar or in vector . there z a rule to differentiate between them. vector:- 1) have magnitude and direction 2) should follow triangle law of addition e.g displacement scalar:- 1) have magnitude 2) doesn't follow triangle law of addition. so, I think pressure should be scalar in quantity cuz whether it has quantity like force which has direction but pressure doesn't follow triangle law of addition.

[@rahulsaini3259]

+Amrish Chandrayan Scalar are Tensor quantity of rank 0 (or order 0). Vector are Tensor of rank 1. But conventionally we call those quantity as tensor whose rank is greater than or equal to 2. Don't mind going too deep into Tensor quantity it can mess up mind of even a graduate or post graduate student very badly. To put in simplest way: The rank (or order) of a tensor is defined by the number of directions you need to fully describe it. You don't need any direction to describe scalar so its a rank 0 Tensor. Vector need 1 direction so its rank 1 tensor. Any quantity which need 2 direction to specify it is Tensor of order 2. and like that. Rank 2 tensor or 4th order tensor. Blah blah blah. Now again, To specify any tensor quantity, you need (3)^(order or rank) coefficients (or numbers) to specify it completely. For scalar, rank is 0, so (3)^0 = 1. So to describe a scalar you just need 1 coefficient. i.e its magnitude only. example: Mass etc. You just need to define 1 number. For vector, rank is 1, so (3)^1=3. So to describe a vector you need 3 number i.e. 3 components. Example: Force etc. You need to define 3 components of force in 3 mutually perpendicular direction to specify it completely. For tensor of rank 2, (3)^2=9. So to describe a rank 2 tensor you need 9 number i.e. 9 components. Example Stress etc. You need to define 9 components of stress. That's done in 3*3 matrix. 3 "normal stress" in 3 mutually perpendicular directions i.e. x, y, z. And 6 "shear stress." Similarly, for Tensor of rank 4, you need to describe (3)^4 = 81 coefficients! Matrix of 9*9 i.e. 81 elements. Too much huh! What about Tensor of rank 9? Believe me that's a nightmare even to any greatest mind of physics. :D FYI: Pressure and stress are different. I happen to listen some portion of video and I overheard sir was saying pressure and stress are same though they are not. Mathematically they are force divide by area but strictly speaking both are different. But upto school level it doesn't make much difference but again its always better if you know something more precisely and accurately. Most students grasp these things taught at school level too much that they have difficulty to grasp the difference between two at post-school level. As the sir was saying, Pressure have no direction but pressure do have direction. In all of fluid mechanics you ever gonna study, pressure is treated as scalar only. But there are some cases (outside general relativity I guess, not sure completely) where pressure is considered as tensor quantity. Again that's not in your scope even upto PhD. So don't bother much and treat pressure as scalar quantity only. Before I forget to tell, I was saying that pressure have direction and its always normal to area. That's precisely the reason why we treat pressure as scalar quantity because its direction is fixed! As the sir was saying pressure act in many or all directions, he meant Pascal's law but didn't stated so. Pressure always act in only one direction that is normal direction. While pressure intensity at a point, in a static fluid is same from all direction. Note that I said at a point. Its known as Pascal's law. When sir defined at somewhere around 41:41 that according to pascal's law pressure at point 1 and 2 should be same. That's completely wrong. That's not pascal's law. I'm saying again, Pascal's law state that at a point, pressure intensity is same from all direction. As a consequence of Pascal's law, you can say that pressure will be same at horizontal plane for a static fluid. That's why if you take a cylinder and make some holes, say 4 holes in 4 directions viz. North, west, south, east; at same level from bottom (in a horizontal plane) so as per pascal's law water from all holes will go out upto same distance. Its a small activity probably you already aware of it. P.S. I haven't listened to whole video, just happen to listen a small portion so I'm not aware if Sir stated Pascal law like I just stated at some later stage. I guess I've wrote a lot. But if you gonna read all of it, you will surely gonna learn something new and I hope your question is cleared by now. Enjoy learning! Ta-da!

[@ramkrishnabose647]

stress is tensor not pressure but we can say it tensor .actually all quantities are tensor.scaler is 0 ranked tensor

[@ramkrishnabose647]

+Rahul Saini can you tell me if 2 ranked tensor exist .where is the 2 direction at same time.is it possible.if so how? please explain

[@rahulsaini3259]

+RAMKRISHNA BOSE stress is tensor of order 2. So to define stress completely you need to define 3^2=9 components. 3 are normal to planes i.e. in X, y, z direction and these are called direct or normal stress and rest 6 are along the planes and are known as shear stress. These 6 shear stresses are along xy plane, yx plane, zy plane, yz plane, xz plane and zx plane. By symmetry and definition of problem xy and yx is same in magnitude, yz and zy are same in magnitude, zx and xz is equal in magnitude. so these 6 unknowns of shear stress reduces into 3 unknowns. we represent all these 9 components of stress tensor in square matrix of size 3x3. you will learn all these in higher study. for time being its alright to have an idea about it. you are already ahead of all those students who think or debate if pressure is scalar or vector or tensor. You know pressure is tensor but behave as scalar. you also get to know that stress is also a tensor and we need 9 components to define stress completely. in your book you calculate stress directly by dividing load by cross sectional area. That's alright because all problems that you get in your school level are such that that they are 1 dimensional problem so you need to specify or find only 1 normal stress. Don't get too much into this concept at this stage. I'm not demotivating you or asking you to stop questioning but pay more attention to things that are more important as of now i.e. basic definitions. if your basics are crystal clear then you will understand all things clearly. Understanding stress completely at school level is not an easy task. its almost impossible frankly unless you are one in million. believe me even a final year student have lots of difficulty in grasping stress completely. Strength of Material (SOM) is a subject that's based entirely on calculation stress and its one of the most difficult and fearful subject and if you go for advance SOM then only god is your savior. 😂 as I said stress is one of the most feared quantity in engineering (or say physics). so for the time being just be happy and enjoy the fact that you aren't dealing with stress monster. 😁😁😁 if you have any query or doubt feel free to ask. I'll try my best to answer in simplest way.

[@rahulsaini3259]

+RAMKRISHNA BOSE one more thing, as you said every quantity is actually tensor. you are right technically but as a convention we call only those quantities as tensors whose order is either 2 or greater than 2. so even though scalar and vector are tensor of order 0 and 1 respectively but we don't refer them as tensor. we call them simply as scalar and vector. to sum up, if you call scalar and vector quantities as tensor then you are correct in puristic sense but wrong in conventional manner. and majority of us go as per conventions. besides pressure is actually a tensor but it behaves as if its a scalar quantity. in much higher study, say in your masters or PhD course, you will get to know some cases or domains of problems which can only be solved by taking pressure as tensor quantity. (don't ask me about those cases. I don't know much about that domain. 😁 ) but in other cases that we study or deal commonly pressure behaves as scalar quantity but its not a scalar.

[@vishalj27]

sir you is great teacher. But can you minimize the strength of vedios, its too long. I am unable to watch your all vedios.

[@anushreematurkar8512]

Vishal Jain .... you must improve your english. ....

[@PraveenKumar-fk5eq]

Praveen

[@omkartripathy8925]

Sir I really like your lectures. I have one question. you have define pressure as tensor. By the same logic electric field produce by a point charge must also be a tensor. Then why we write electric field as a vector quantity. Can you please explain ?

[@omkartripathy8925]

Thank u sir. you r really a great teacher.

[@airtel1730]

SIR, thanks a lot .

[@anushreematurkar8512]

pressure is a scalar quantity. ...but pressure stress is a tensor.....

[@muntahanazir4719]

when we insert a body with a hole filled with liquid in a liquid container water will move out from the whole as it will go from higher pressure to lower presure

[@saarthiclasses17]

👍

[@aadityashriwastav349]

Sir pressure is a scaler quantity

[@priyankakunwar3148]

Sony Shriwastava no this is a tensor

[@upanyastajan9248]

Immortal personality

[@quantlfc]

great !!!

[@reactionking3343]

GREAT SIR

[@sidharthmehra4710]

Thank you Regards Sidharth

[@Agriculturebooksreview]

sir आप बहुत ही प्यार से पढ़ाते हैं ओर आपका अनुभव दिखता है किर्पया आप अपनी आवाज को ठीक करने लिए आप से निवेदन है की आप कॉलर माइक का प्रयोग करे हमें सुनने में बहुत अच्छा लगेगा

[@prashantpal5282]

thank you sir you r a good teach

[@riskyprince7564]

u r great

[@basilelias01]

thank you very much sir....

[@bethebest4581]

best lecture

[@rajbaba1806]

Sir u r amazing

[@peacefuldisputes7102]

SIR ME from pakistan ,,really very impressive lectures......live long

[@gameratoz0]

the teacher is good

[@akhileshchauhan1070]

Thanks sir...............................

[@jzwillows]

I suggest differentiating between the two categories of fluids - gases and liquids - since their behavior with respect to pressure is completely different since the former is compressible and the latter is not. With a gas the force its exerts against the container walls is the same as the gaseous pressure since the connection between gaseous pressure and pressure exerted by the gas against the walls has a facilitator - the property of compressibility: add more molecules to a containerized gas and the pressure increases, pushing harder against container walls. With a liquid, there is no such facilitator to connect the internal pressure to the pressure exerted by the fluid against the container walls. Thus with a liquid, regardless of container shape, the internal pressure is a function of depth but not connected to the pressure exerted by the body of liquid against the walls. For example, with a container narrowing at the top the pressure against the bottom is a function of the mass of liquid directly above the bottom. Were it a function of internal (hydrostatic) pressure it would be a function of only depth (I know text books state it is) but if it were a function of depth, the force the liquid exerts against the bottom would exceed the weight of the liquid directly above the bottom and it is impossible for a liquid to exert a force greater than the weight since the laws of physics dont allow that (the only way a liquid could push harder than the push from its weight would be by one of 2 ways: expanding or increasing in density, neither of which is possible in a liquid). Think about it. I provide details in a video titled Elementary Hydrostatics.

[@adarshsem_uk09]

thanks sir very much

[@SanjeevKumar-zd6xu]

Good

[@saggulyricalfeel5309]

va maja a gaya