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Target IIT-JEE (Chat Room)


Since we have to compete in jee in an all India level , it is quite obvious that we want the views of others , we want to know about our competitors.

So I have created this as a Communication platform for all those preparing for IIT - JEE.

  • You can talk to the ones personally by mentioning their link. And giving them the time when you will be online .

  • you can ask general questions.

  • you can keep your communication personal by deleting it after your work is over.

  • Anyone can join this chat room and can even invite his friends . For joining just save this note with you (optional).

  • You can even ask your doubts. In any chapter(Restriction :you cannot discuss solution to Brilliant questions here , but you can share the link and ask them to come there )

  • I see ,we don't always get a reply to our question , but if we all be at a single chat room we would definitely get a reply

Note : This chat room is also started on slack , There we can communicate better!!! To join slack click here

Note by Aniket Sanghi
5 months, 1 week ago

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Doubt:

Please give a hint.

A uniform rid of length L lies on a smooth horizontal table.A particle moving on the table strikes the rod perpendicularly at one end and stops. Find the distance travelled by the center of rod by the time it turns through a right angle. Harsh Shrivastava · 5 months, 1 week ago

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@Harsh Shrivastava Use the following equations to find \( \omega \):

  1. Conservation of linear momentum

  2. Conservation of angular momentum (about a point just above the COM of the rod, in the air, so that the point taken is stationary wrt ground and there is no angular impulse)

Then use \( \theta = \omega t \) to get the time taken by it to rotate through \( \theta \)

And finally, \( S = v t \), where \( v \) is the velocity of the COM of the rod after collision, to find the distance travelled Ashish Gupta · 5 months, 1 week ago

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@Ashish Gupta Ohk got it!

Thanks a ton. Harsh Shrivastava · 5 months, 1 week ago

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@Harsh Shrivastava RM is tough right? :( I hardly solve few fully independently. Nihar Mahajan · 5 months, 1 week ago

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@Nihar Mahajan Same here :(

Noatter how hard I try, I can't do physics independently without any aid. Harsh Shrivastava · 5 months, 1 week ago

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@Harsh Shrivastava No problem. Glad to help. Ashish Gupta · 5 months, 1 week ago

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What is the exam pattern of JEE 2017? Nihar Mahajan · 5 months, 1 week ago

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@Nihar Mahajan you never know jee pattern even 1 day before JEE exam (adv. obviously!) Akul Agrawal · 5 months, 1 week ago

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@Akul Agrawal Yes you are right. No one expected last year's pattern. Aditya Kumar · 5 months, 1 week ago

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@Nihar Mahajan What is the exam pattern of JEE 2020? :P Svatejas Shivakumar · 5 months, 1 week ago

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@Svatejas Shivakumar What is the exam pattern of JEE 2018? Harsh Shrivastava · 5 months, 1 week ago

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General question:

We all are usually confused whether the book we are referring is nice or not.........especially in the critical month before jee advanced.........let's here share the books we prefer along with a reason why we prefer it Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi Maths - cengage (lot of q to practice along with solutions)

Physics - cengage (lot of q to practice along with their solutions, nice theory )

Chemistry-

Physical- P bahadur (Everything in few pages)

Inorganic - NCERT ( Best explanation)

Organic - Cengage ( Authentic theory) Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi Physics- HC Verma (Most Authentic Theory and No errors at all and best theoretical Problems are framed from It Only) DC Pandey (Practice Nice questions with solutions)

Chemistry- RC Mukherjee (Physical- Has Almost all the variety of problems and important concepts)

Solomon's And fryhle (Organic- Detailed Explanantion and nice subjective problems)

Inorganic- its none of my buisness ! :P (but still i like ncert)

Maths- I dont get time to solve problems of maths from books (my coaching sheets, packages and archive are more than enough i think)

But still i refer to TMH For algebra for some mind bending problems and arihant for calculus for good explanation of concepts Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal @Prakhar Bindal what is the color of the cover page of soloman and fryle Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi Green

This book

http://www.amazon.in/Solomons-Fryhles-Organic-Chemistry-Advanced/dp/8126541814?tag=googinhydr18418-21 Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal What about the red one? Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi My teacher Suggested to use this as original solomon's has some portion out of JEE Syllabus. Also he gave us a option between Solomon and Morrison And Boyd. My friends are using Morrison and they are finding that useful. I Also saw the book and seemed nice. Also Similar to solomon morrison has a lot of portion not in our syllabus so our teacher recommended to use solomon only but if not available then he said to go for morrison and boyd

http://www.flipkart.com/organic-chemistry-english-7th/p/itmdmyjz99fnszs6 ]\ Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal What is your position in your class and what is your confidence level in organic Aniket Sanghi · 5 months, 1 week ago

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@Prakhar Bindal @Prakhar Bindal I have found a mistake in HC Verma. Saarthak Marathe · 5 months, 1 week ago

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@Saarthak Marathe Can you tell where? ( My Sir told that HC Verma Is 99.9% Authentic) Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal One is in the capacitor chapter .The other is in the SHM chapter,the question where two wheels are rotating and a rod is placed on it,the direction of rotation is given wrong (this question was copied wrongly from irodov.) Saarthak Marathe · 5 months, 1 week ago

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@Saarthak Marathe can you tell, which one in capacitor is wrong, i agree with the second one , i solved it from irodov. Shubham Dhull · 1 week ago

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@Prakhar Bindal @Prakhar Bindal Bhaiya, What about theory of Physical Chemistry? RC Mukherjee has little theory, will it be sufficient with my coaching packages and NCERT? Pankil Kalra · 5 months, 1 week ago

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@Pankil Kalra Well I Never needed any book for theory in physical. NCERT Is nice. If you want some more theory then i would Suggest to go for OP Tandon Or P Bahadur (OP Tandon's physical is nice DONT Ever buy its organic book it would make your head go round!! ) Prakhar Bindal · 5 months, 1 week ago

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@Pankil Kalra P bahadur would be nice for theory Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi same here but I prefer Ms Chauhan for organic Prashant Kr · 5 months, 1 week ago

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@Aniket Sanghi Physics- HC Verma , i.e irodov (sometimes) ,arithant publication by d.b. singh (head of science centre kota) vidyamandir modules, past 37 year iit jee questions, NCERT chemistry- i'm very poor at it, i don't really care but sometimes read my modules. NCERT maths- vidyamandir modules, past 37 year papers , TMH ,NCERT higher algebra (hall and knight) i'm not that much of a studious kid :) Shubham Dhull · 1 week ago

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@Aniket Sanghi @Aniket Sanghi @Prakhar Bindal Thank you both :D Pankil Kalra · 5 months, 1 week ago

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@Aniket Sanghi I would say,

Maths-Cengage(JEE type questions)

Physics-Resnick Halliday,Feynman(awesome concepts),HC Verma(conceptual questions),DC Pandey(JEE type),Irodov,Krotov(for high thinking)

Physical Chemistry-P Bahadur(many problems)

Inorganic Chemistry-JD Lee(concepts),OP Tandon(mostly for facts)

Organic Chemistry-Solomons(concept),Himanshu Pandey(many JEE type questions)

To be honest, for physics, every book copies from Irodov,Krotov,Resnick Halliday(including HC Verma,DC Pandey) so I would suggest to solve many questions from these books even if they are difficult. Saarthak Marathe · 5 months, 1 week ago

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How many of you give full tests of Fiitjee?

Particularly of 25th april 2016 Mayank Singh · 5 months ago

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@Mayank Singh mention some names to make them aware Aniket Sanghi · 5 months ago

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@Aniket Sanghi I don't know who all do.

Leave it Mayank Singh · 5 months ago

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Salute to the person who got the idea to Cretate this chat room . please can anyone tell the person who created this chat room . a wonderful idea . thank-you this chat room helped me a lot Sai Kiran · 5 months, 1 week ago

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@Sai Kiran Thanks! I hope it will be helpful to all :) Aniket Sanghi · 5 months, 1 week ago

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I want to clear a doubt in this question

please read my comment and tell where i am going wrong.

Thanks. Neelesh Vij · 5 months, 1 week ago

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Is there any PDF or eBook which can help me improve my Coordinate Geometry for JEE Advanced? Since it's right around the corner and is generally where I lose marks in Maths, I'm wondering if there is any such resource or even a good question bank or something of the sort which can help me make it my strong point (most people say it's the easiest part of Maths). Ashish Gupta · 5 months, 1 week ago

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A good mechanics problem :

A weightless rod of length \(l\) with a small load of mass m at the end is hinged at point as shown in the figure and occupies a strictly vertical position, touching a body of mass M. A light jerk sets the system in motion. For what mass ratio M/m will the rod form an angle \(x = 30 ^{\circ}\) with the horizontal at the moment of the separation from the body?What will be the velocity u of the body at this moment? Friction should be neglected.

Please help me with this problem.

@shubham dhull @Prakhar Bindal @Aniket Sanghi Harsh Shrivastava · 2 days, 13 hours ago

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@Harsh Shrivastava M/m = 4 v = (1/2)(gl/2)^0.5 Aniket Sanghi · 2 days, 12 hours ago

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@Aniket Sanghi why don't u come over slack ? Shubham Dhull · 2 days, 12 hours ago

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@Aniket Sanghi Oh thanks for your solution!

Sry I didn't knew that this prob was already posted on b'llant. Harsh Shrivastava · 2 days, 11 hours ago

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@Aniket Sanghi can u give link to prob plz Shubham Dhull · 2 days, 12 hours ago

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@Shubham Dhull I can't do that ! As that would be cheating ;) Aniket Sanghi · 2 days, 12 hours ago

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@Aniket Sanghi just the link? Shubham Dhull · 2 days, 12 hours ago

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@Shubham Dhull 1st tell me , why do u want that? Aniket Sanghi · 2 days, 12 hours ago

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@Aniket Sanghi to solve it myself Shubham Dhull · 2 days, 12 hours ago

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Which Resnick Halliday is better? The one written exclusively for jee advanced or one which is not? Harsh Shrivastava · 5 months, 1 week ago

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@Harsh Shrivastava Best is Resnick Halliday Crane ( I will not suggest Walker neither do I criticise it). Akul Agrawal · 5 months, 1 week ago

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@Harsh Shrivastava Go for the original one. That'll help you for NSEP+JEE. Aditya Kumar · 5 months, 1 week ago

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@Aditya Kumar https://www.flipkart.com/physics-volume-i-5th-english/p/itmdytmvygedvpch?pid=9788126510887&lid=LSTBOK9788126510887QNNK0T

Is this good? Harsh Shrivastava · 5 months, 1 week ago

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@Harsh Shrivastava I have Resnik Walker Hallinday. This is different. I have an old book. So I don't know about the new one. Aditya Kumar · 5 months, 1 week ago

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@Aditya Kumar OK so do you find it useful?

If you have few mins to spare, can you please give me a review about your book? Thanks! Harsh Shrivastava · 5 months, 1 week ago

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@Harsh Shrivastava Yes it was useful only for theory. Good for clearing concepts. Aditya Kumar · 5 months, 1 week ago

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@Aditya Kumar Ohk thanks! Clearing of concepts is what I need! Harsh Shrivastava · 5 months, 1 week ago

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I see that many students find themselves weak in chemistry , so, let's practice chemistry

A person who will answer the question correctly with its solution will have the right to post the next question, followed by another.and sequence would go on ............ Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi 1 st question : how many radial nodes are present in the orbital represented as : n = 5 , l = 2 , m = 0. Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi number of radial nodes = n-l-1 = 2.

Number of angular nodes = l = 2

Total Nodes (Excluding the one at infinity) = 4

Total Nodes (Including Infinity one) = n = 5 Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal dz2 has no nodal planes it has two nodal conical surface.. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat Can You Please elaborate? and can you tell from where can i learn these things about nodal planes,nodes etc? Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal i learnt it from J.D.Lee(inorganic chem book)(i have the orange one but if you have black you can post hundreds of question which would have 0 solvers but its not for jee orange one is) but for now you may look "https://www.physicsforums.com/threads/classifying-electron-orbitals-by-nodes.621771/". Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat So should I prefer orange or the black one for jee or is their any other (JD lee) please can you share the

@aryan goyat @Mayank Singh Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi I've black Mayank Singh · 5 months, 1 week ago

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@Mayank Singh Is that better than orange one? What's your analysis Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi never ceen the orange Mayank Singh · 5 months ago

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@Aniket Sanghi if you love doing chemistry and really enjoy the inorganic part go for black i also wanted to have it but i didn't knew at that time. But it has some topics which jee does not test. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat I want to be confined with jee syllabus and don't want to miss anything , then which one to prefer Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi orange one :) Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat And what's your expected score in jee main Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi i am in 12 now and will appear for jee in 2017. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat I too have orange one :) For JEE Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal Is the black one better or the orange one?

And were you knowing aryan goyat is of our age (I thought he is 1 year ahead) Aniket Sanghi · 5 months, 1 week ago

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@Prakhar Bindal it's the very basic of nodes , you can find it in the great " NCERT " textbook if you see it my bro. Shubham Dhull · 1 week ago

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@Aryan Goyat Right! Can you elaborate about nodal conical suface (I would like to know) Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi i hope you know the shape of 5dz2 orbital just make 2 cones such that it does not touch the electron density. you may google for the pics. Aryan Goyat · 5 months, 1 week ago

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@Prakhar Bindal Wrong answer! Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi But why? Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal I think you didn't try my set ! Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi you have asked here radial nodes which is n-l-1 may it be 5z2. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat What 5z2 Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi its 5dz2 . Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat It is definetely 5dz2 as m =0 is for dz2 Aniket Sanghi · 5 months, 1 week ago

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A common doubt : How to prepare inorganic chemistry and from where

@Sandeep Bhardwaj Aniket Sanghi · 5 months, 1 week ago

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What is adv. Arpan Manchanda · 5 months, 1 week ago

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@Arpan Manchanda What are you asking?? Be clear Aniket Sanghi · 5 months, 1 week ago

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I have 2 doubts. Firstly, in this Physics question question, the answer comes out as \( R^2 \sqrt{\frac{2 P \cdot g}{3T}} \), right? Secondly, in this Maths question, is there any better way of solving it other than taking partial derivatives, solving the simultaneous equations in \(x,y\) and plugging them in to get the answer? Ashish Gupta · 5 months, 1 week ago

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@Ashish Gupta For the first one,the answer comes out as \(\displaystyle {R}^{2}\sqrt{\frac{Pg}{3T}} \) because, it is a bubble and as there are two layers, while solving we have to take \(2*2\pi*R\). Saarthak Marathe · 5 months, 1 week ago

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Is reading NCERT for inorganic enough? Aditya Kumar · 5 months, 1 week ago

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@Aditya Kumar JD LEE + NCERT + Your institute's notes + Previous years papers = total JEE advanced inorganic chemistry Mayank Singh · 5 months, 1 week ago

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@Mayank Singh Thanks I was doing JD LEE now. I was not sure whether that level would come. Now I shall read it more seriously. Aditya Kumar · 5 months, 1 week ago

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@Aditya Kumar i dont think so Mayank Singh · 5 months, 1 week ago

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@Aditya Kumar We are told that's enough for rest our fiitjee materials fill the vacant spaces Aniket Sanghi · 5 months, 1 week ago

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Nice Mayank Singh · 5 months, 1 week ago

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@Gauri shankar Mishra It would be called cheating if we post a solution to a brilliant problem here, moderators would delete it Mayank Singh · 5 months, 1 week ago

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@Mayank Singh Sorry Sir Gauri shankar Mishra · 5 months, 1 week ago

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@Mayank Singh Yes you are right. @Gauri shankar Mishra discuss the solution there itself. If you want you can tag someone you want. Please don't discuss solutions of brilliant problems here or else I shall delete them. Aditya Kumar · 5 months, 1 week ago

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@Aditya Kumar Sorry Sir Gauri shankar Mishra · 5 months, 1 week ago

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How is your study going? Rishabh Deep Singh · 5 months, 1 week ago

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Invitation to @Prakhar Bindal @Gauri shankar Mishra @Aditya Kumar @aryan goyat @Mayank Singh and all who are interested are welcomed Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi Thats a nice Initiative Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal Great work Gauri shankar Mishra · 5 months, 1 week ago

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@Aniket Sanghi @Adarsh Kumar @Kalash Verma @Nihar Mahajan Harsh Shrivastava · 5 months, 1 week ago

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@Aniket Sanghi @Calvin Lin @Andrew Ellinor @Ronak Agarwal @Nishant Rai @Sandeep Bhardwaj @ Deepanshu Gupta @David Mattingly

You all are experts and our seniors, We need and expect help from you ............. Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi Sure. Always happy to help :) Sandeep Bhardwaj · 5 months, 1 week ago

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@Aniket Sanghi @aryan goyat Prakhar Bindal · 5 months, 1 week ago

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A spring of mass m is pulled such that a given instant, velocity of both of its end is v in the opposite direction. Find the kinetic energy of the spring.

@Aniket Sanghi @Prakhar Bindal Harsh Shrivastava · 1 week ago

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@Harsh Shrivastava I will suggest you to join slack , there you will find many people online every time who will feel it their pleasure to clear yr doubts.

Its link is mentioned in this discussion start. Aniket Sanghi · 1 week ago

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@Aniket Sanghi i joined it but nothing happens at all . Shubham Dhull · 1 week ago

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@Harsh Shrivastava Thanks a ton guyz!

I hope I don't disturb you when I ask my doubts? Harsh Shrivastava · 1 week ago

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@Harsh Shrivastava Nahh its my free time. i am watching Taarak Mehta Prakhar Bindal · 1 week ago

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@Prakhar Bindal if it's your free time bonus: prove the result i am using. Shubham Dhull · 1 week ago

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@Harsh Shrivastava You can solve it by integration

Use the property : In spring the velocity of any element dx at a distance x from the point of non-zero velocity is proportional to x.

Now, find the kinetic energy of this element and then integrate to get net kinetic energy.

The property I told you above can easily be proved and I have proved it in one of your doubt discussion

@Harsh Shrivastava Aniket Sanghi · 1 week ago

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@Aniket Sanghi is'nt my method correct? Shubham Dhull · 1 week ago

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@Shubham Dhull You are Using one result to prove another. He wants the proof of the result you are preassuming to be true! Prakhar Bindal · 1 week ago

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@Harsh Shrivastava You can assume that velocities to vary linearly along the length of spring. Hence consider an element at a distance x from one of the end of the spring , write its velocity as a function of x , Write its kinetic energy as 1/2dmv^2 and integrate from 0 to l to get total kinetic energy.

I Would say to remember this result as it is quite helpful in SHM Problems Involving spring with mass. But Derivation is Important too for Proper Understanding Purposes Prakhar Bindal · 1 week ago

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@Harsh Shrivastava mv^2/6? Prakhar Bindal · 1 week ago

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@Prakhar Bindal Hey are free for next half hour?

I have a problem that's bugging me since evening.

A physics problem. Harsh Shrivastava · 1 week ago

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@Harsh Shrivastava Sorry but i am a bit busy these days (AIITS This monday + revision of class 11) . you can post here i will do as soon as i get some more time Prakhar Bindal · 1 week ago

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@Prakhar Bindal No prob :) Harsh Shrivastava · 1 week ago

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@Harsh Shrivastava i can help if you want ! Shubham Dhull · 1 week ago

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@Shubham Dhull Sure!Thanks!

I'll post the prob after 30 mins, havta go out. Harsh Shrivastava · 1 week ago

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@Harsh Shrivastava i think i have waited much than you said Shubham Dhull · 1 week ago

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@Shubham Dhull Sorry bro, net was down. Harsh Shrivastava · 2 days, 13 hours ago

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@Harsh Shrivastava ok i'll be waiting uptill then Shubham Dhull · 1 week ago

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@Prakhar Bindal Correct! Please give a hint. Harsh Shrivastava · 1 week ago

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@Harsh Shrivastava yes me too mv^2/6 as you must be knowing the contribution of a spring in any energy is m/3. and if we break it in 2 parts , you can do it now hope it helps. Shubham Dhull · 1 week ago

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@Shubham Dhull Why is the contribution m/3? Harsh Shrivastava · 1 week ago

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@Harsh Shrivastava because of its twists and turns, the linear contribution of mass is only m/3 , you can google if there is any proof but it would be great if you try to remember it . hope it helps ! Shubham Dhull · 1 week ago

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Can someone please post a solution to this problem . please!!!! Gauri shankar Mishra · 4 months, 3 weeks ago

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try this https://brilliant.org/problems/no-story-this-time/?ref_id=1178336 Mayank Singh · 5 months ago

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@Mayank Singh Again let it get some rating :P Prakhar Bindal · 5 months ago

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@Prakhar Bindal without rating , dont we get the credit Aniket Sanghi · 5 months ago

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@Aniket Sanghi u get 100 points Mayank Singh · 5 months ago

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@Prakhar Bindal ok ok Mayank Singh · 5 months ago

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Hey please can anyone help me with this

The number of normals to the curve 3y^3 = 4x which passes through (0,1) is

Answer Given = 1

My Approach found at slope of normal at any point , wrote its equation and passed through (0,1) . i obtained a 5 degree equation!

Also i entered that equation into wolfram alpha which showed me that only 1 real root exists. How?

@Aniket Sanghi @rohit kumar @Mayank Singh @aryan goyat @Akul Agrawal Prakhar Bindal · 5 months ago

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@Prakhar Bindal Hey guys me and aniket had a discussion about this problem . We actually arrived at the answer but the only thing that is left is that we have assumed that atleast one normal will exist in the interval x>0 and y>0 . can we prove that the atleast normal has to exist in this interval? cant it be like no normal can be drawn to the curve

@rohit kumar @Mayank Singh @aryan goyat @Akul Agrawal @Aniket Sanghi Prakhar Bindal · 5 months ago

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@Prakhar Bindal Its quite easy to make graph of \({ y }^{ 3 }=\frac { 4 }{ 3 } x\) (I am sure you can do it orally!). And as the function is monotonic, you can easily come to the answer (try once). Akul Agrawal · 5 months ago

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@Akul Agrawal Bhaiya i did not got the answer by your method but thought of another way. The 5 degree equation that i was getting was strictly increasing for all real numbers and when x tends - infinity it also tended to -infinity and similar was for +infinity case. Hence it will cross the x axis only once as function is monotonically increasing.

But i want to know your method as it seems quite short . Can you please elaborate ( i have just started learning calculus)

Thanks! Prakhar Bindal · 5 months ago

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@Prakhar Bindal Prakhar I didid it by graph , I first draw the graph of the eq. Then you can see that the graph changes its concavity at x= 0 so you can easily observe that it can have only one normal at x>0 (graph is monotonically increasing) Aniket Sanghi · 5 months ago

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@Aniket Sanghi What is relation between monotonicity and normals? . why will it have only one normal for x> 0 please explain Prakhar Bindal · 5 months ago

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@Prakhar Bindal Graph

Clearly y=0 (x axis) is normal at origin. Now see how normal changes as we move left or right( it would be easy to see this as function is monotonic). (As we move right, the y- intercept of normal will keep on increasing) Akul Agrawal · 5 months ago

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@Akul Agrawal but x axis does not pass through (0,1) Prakhar Bindal · 5 months ago

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@Akul Agrawal Please can you be more detailed? i realized that function is monotonically increasing as first derivative >0

@Akul Agrawal Prakhar Bindal · 5 months ago

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Those who love chemistry are invited to try these (BEST OF JEE - ADVANCED) Aniket Sanghi · 5 months, 1 week ago

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Today Rajdeep Asked me a question in which we were required to compare the acidic strength of H2SO4 , HCl AND H3PO4. I Was quite easily able to tell that H3PO4 would be the weakest acid. but was struck in comparing acidic strength of H2SO4 And HCl. i searched internet and got confused as all give a different answer. can any one please help?

@aryan goyat t @Aniket Sanghi @rohit kumar @Aditya Kumar @Abhineet Nayyar Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal i think the book you mentioned above ie solomons can help , checkout the table within it it is H2SO4 which is more stronger.(table 3.1 in 10th edition) Aryan Goyat · 5 months, 1 week ago

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@Aniket Sanghi mines are similar to prakhar with an exception that in physics i don,t prefer books and in inorganic i stick to J.D.Lee(the best book in inorganic) Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat I thought you were 1 year ahead! Are you in fiitjee Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi yes fiitjee jaipur. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat What's your AIITS Rank history Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi near 50s (average) Aryan Goyat · 5 months, 1 week ago

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@Aniket Sanghi and your histroy Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat Top 20s Aniket Sanghi · 5 months, 1 week ago

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@Aryan Goyat please provide me the link of it. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat https://www.quora.com/Why-is-hydrochloric-acid-stronger-than-sulphuric-acid-even-though-sulphuric-acid-should-dissociate-to-produce-more-hydrogen-ions Prakhar Bindal · 5 months, 1 week ago

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@Aryan Goyat Common strong acids[edit] This is a list of strong acids with pKa < -1.74, which is stronger than the hydronium ion, from strongest to weakest. Perchloric acid HClO4 (pKa ≈ −10)[5] Hydroiodic acid HI (pKa = −9.3)[2] Hydrobromic acid HBr (pKa = −8.7)[2] Hydrochloric acid HCl (pKa = −6.3)[2] Sulfuric acid H2SO4 (first dissociation only, pKa1 ≈ −3)[6] p-Toluenesulfonic acid (pKa = −2.8) Organic soluble strong acid Methanesulfonic acid (pKa = −1.92) Liquid organic strong acid[7] Almost strong acids[edit] from wikipedia Prakhar Bindal · 5 months, 1 week ago

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@Aryan Goyat That's the problem . I Looked up Wikipedia it says HCl which even confuses me more Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal Wikipedia is not authentic ,it can be edited! Aniket Sanghi · 5 months, 1 week ago

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@Prakhar Bindal My Book (Cengage (Authentic) ) says H2SO4(pKa = -9) is stronger acid than HCl (pKa = -7)

Different source may give different results as you may know acidity also depends on the solvent.....Like H2SO4 and HCL will differentiate equally in H2O (high dielectric constant) , so you can't use H2O to compare acidity. Similarly may be diff sources are based on diff solvents. Aniket Sanghi · 5 months, 1 week ago

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@Aniket Sanghi I Also Thought H2SO4 Because it is diprotic and high resonance on conjugate base let me assume it to be true as it is the same in solomons Prakhar Bindal · 5 months, 1 week ago

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@aryan goyat Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta u there? Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta yes Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat I Mean to say for pure rolling bottom most point must be at rest wrt the surface it is performing pure rolling also the conditon a = R*Alpha should get satisfied . How can they both be simultaneously True? Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta why cannot it be see the what we mean by a=alph*R is dv/dt=R.dw/dt

dv=Rdw

adding v to both side v+dv=Rdw+v

v+dv=Rdw+wR

v(after time dt)=w(after time dt)R Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat Ok . My confusion is basically that during pure rolling we say that point of contact remains at rest hence force of friction should not act but we take in several problems like i gave you the previous one Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta then why dont you look at the object just after a time dt you find that the object is not doing pure rolling so here comes friction within a negligible time interval which even we cant measure and we would have to say that both act simultaneously. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat Ok . In the Football Question We Have said that as pure rolling has started after first collision with rough ground so the bottom most point must have come to rest and hence it will be at rest when it again collides with rough ground. Hence there is no reason why friction must act. Cant we compare the two cases?(This football one and situation that i gave you). here also Once pure rolling started on horizontal surface the bottom point comes to rest hence there is no reason why friction should act Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta next did you find any horizontal force which is making it out of rolling in time dt. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat in case of football field just after time t however long or small it may be the sphere will go on pure rolling, however it is not so here even after a small time dt the pure rolling is off. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat i think i need some rest . i will talk to you tomorrow in this regard as i am feeling exhausted. thanks for taking out your precious time and having discussion in my silly concept Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta as much i know "no question is a silly question" Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat I Have Done The Following Analysis.

For Pure rolling on horizontal surface

Case.1 An external force is acting

In This case friction may or may not act. It All depends on the point of application of horizontal force.

Case 2. An External Is Not Acting

In This Case Friction Should Not act if body is continuing pure rolling. Because Friction will provide a and alpha in same direction hence a= R*Alpha can never be true.And once pure rolling started friction Friction will become zero so as the condition remains true (now a and alpha will become zero as there is no force) hence it will continue on to uniform pure rolling ( not accelerated )

External force does not includes friction

Is This analysis correct? Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta absolutely correct. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat Thanks a lot @aryan goyat because of you my rolling concept became clear Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta i told you earlier too no need of thanks. Aryan Goyat · 5 months, 1 week ago

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@Pankaj Gupta Ab to tujhe samajh me aa gaya? Prakhar Bindal · 5 months, 1 week ago

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@Prakhar Bindal Yes i got it tujhe samjhana hi nahi aata :P Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta Maybe i am not good at explaining Prakhar Bindal · 5 months, 1 week ago

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@Pankaj Gupta not after first after second. Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat Yeah i meant first collision with rough ground Pankaj Gupta · 5 months, 1 week ago

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@Pankaj Gupta sorry i did not noticed the phrase "rough surface" . Aryan Goyat · 5 months, 1 week ago

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@Aryan Goyat no problem i just want your opinion on comparison in between two cases if i apply your explanation to our simple case of pure rolling on horizontal surface Pankaj Gupta · 5 months, 1 week ago

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@Aryan Goyat So My Question is According to you if friction does not act in that case the condition a = R*Alpha wont get satisfied for pure rolling right? . But as the bottom most point is at rest so why would friction act? Pankaj Gupta · 5 months, 1 week ago

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