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 !! Give me your email ID if you want to be a part of it!

## Comments

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TopNewestDoubt:

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 · 9 months, 1 week ago

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Conservation of linear momentum

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 · 9 months ago

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Thanks a ton. – Harsh Shrivastava · 9 months ago

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– Nihar Mahajan · 9 months ago

RM is tough right? :( I hardly solve few fully independently.Log in to reply

Noatter how hard I try, I can't do physics independently without any aid. – Harsh Shrivastava · 9 months ago

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– Ashish Gupta · 9 months ago

No problem. Glad to help.Log in to reply

What is the exam pattern of JEE 2017? – Nihar Mahajan · 9 months, 1 week ago

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– Akul Agrawal · 9 months, 1 week ago

you never know jee pattern even 1 day before JEE exam (adv. obviously!)Log in to reply

– Aditya Kumar · 9 months, 1 week ago

Yes you are right. No one expected last year's pattern.Log in to reply

– Svatejas Shivakumar · 9 months, 1 week ago

What is the exam pattern of JEE 2020? :PLog in to reply

– Harsh Shrivastava · 9 months, 1 week ago

What is the exam pattern of JEE 2018?Log in to reply

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 · 9 months, 1 week ago

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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 · 9 months, 1 week ago

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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 · 9 months, 1 week ago

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@Prakhar Bindal what is the color of the cover page of soloman and fryle – Aniket Sanghi · 9 months ago

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This book

http://www.amazon.in/Solomons-Fryhles-Organic-Chemistry-Advanced/dp/8126541814?tag=googinhydr18418-21 – Prakhar Bindal · 9 months ago

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– Aniket Sanghi · 9 months ago

What about the red one?Log in to reply

http://www.flipkart.com/organic-chemistry-english-7th/p/itmdmyjz99fnszs6 ]\ – Prakhar Bindal · 9 months ago

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– Aniket Sanghi · 9 months ago

What is your position in your class and what is your confidence level in organicLog in to reply

@Prakhar Bindal I have found a mistake in HC Verma. – Saarthak Marathe · 9 months ago

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– Prakhar Bindal · 9 months ago

Can you tell where? ( My Sir told that HC Verma Is 99.9% Authentic)Log in to reply

– Saarthak Marathe · 9 months ago

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.)Log in to reply

– Shubham Dhull · 4 months ago

can you tell, which one in capacitor is wrong, i agree with the second one , i solved it from irodov.Log in to reply

– Pankil Kalra · 9 months ago

@Prakhar Bindal Bhaiya, What about theory of Physical Chemistry? RC Mukherjee has little theory, will it be sufficient with my coaching packages and NCERT?Log in to reply

– Prakhar Bindal · 9 months ago

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!! )Log in to reply

– Aniket Sanghi · 9 months ago

P bahadur would be nice for theoryLog in to reply

– Prashant Kr · 9 months ago

same here but I prefer Ms Chauhan for organicLog in to reply

– Shubham Dhull · 4 months ago

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 :)Log in to reply

@Aniket Sanghi @Prakhar Bindal Thank you both :D – Pankil Kalra · 9 months ago

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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 · 9 months ago

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How many of you give full tests of Fiitjee?

Particularly of 25th april 2016 – Mayank Singh · 9 months ago

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– Aniket Sanghi · 9 months ago

mention some names to make them awareLog in to reply

Leave it – Mayank Singh · 9 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 · 9 months ago

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– Aniket Sanghi · 9 months ago

Thanks! I hope it will be helpful to all :)Log in to reply

I want to clear a doubt in this question

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

Thanks. – Neelesh Vij · 9 months 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 · 9 months ago

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So, nobody is gonna add me , OK, fine by me ! – Shubham Dhull · 2 months, 2 weeks ago

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How do I increase my problem solving speed? – Swapnil Das · 2 months, 2 weeks ago

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@Aniket Sanghi @Harsh Shrivastava @Prakhar Bindal add me to slack again plz, i miss talking to you guys and prakhar , just coz of motivational words you said to me i got 86 in chem out of 120 ad my teacher really praised me coz it was one of the highest marks anybody got there and i got 109 in physics too , my teacher said i was one of the brightest minds in the country as far as physics goes ! i am really happy and motivated ! \( \ddot smile \) – Shubham Dhull · 2 months, 2 weeks ago

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– Harsh Shrivastava · 2 months, 2 weeks ago

Kudos!Log in to reply

– Shubham Dhull · 2 months, 2 weeks ago

Thanx motivation baba !Log in to reply

– Aniket Sanghi · 2 months, 2 weeks ago

Give me your email IDLog in to reply

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– Aniket Sanghi · 2 months, 2 weeks ago

It's showing me , that sending invites failed for this email id and in the bottom written email id, I sent the invite Which one is right email?Log in to reply

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@Swapnil Das , you add him . I am not able to send him the invite – Aniket Sanghi · 2 months, 2 weeks ago

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– Swapnil Das · 2 months, 2 weeks ago

I'm on tab, can't send now.Log in to reply

– Shubham Dhull · 2 months, 2 weeks ago

man..... then when ??Log in to reply

– Swapnil Das · 2 months, 2 weeks ago

10 days.Log in to reply

– Shubham Dhull · 2 months, 2 weeks ago

what the heck ?? ca't you do something about it??Log in to reply

@Swapnil Das you there ?? plz reply i'll have to go now ! – Shubham Dhull · 2 months, 2 weeks ago

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– Shubham Dhull · 2 months, 2 weeks ago

there is a guy whose name is i form of a email id anytime i write my id his name spoils it all ! ( he gets marked !! )Log in to reply

– Aniket Sanghi · 2 months, 2 weeks ago

To me it is showing , sending invites failed !Log in to reply

@Aniket Sanghi @shubham dhull @Prakhar Bindal Can i also join your chat room?

If yes, then please tell me how? – Harsh Shrivastava · 2 months, 2 weeks ago

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– Shubham Dhull · 2 months, 2 weeks ago

i have deleted my account there as i thought i am not doing justice to myself, watching po** every time and the spending time, chatting with people, whenever i was not doing that "thing mentioned above" . i feel pity when i think where i have fallen from a state science Olympiad topper to my current state . sorry for saying it here but i think you r my friends and i can let all my feeling with you ! :(Log in to reply

– Harsh Shrivastava · 2 months, 2 weeks ago

It is not too late, you can mend yourself, i have seen many people mending their ways and being back on track.May God be with you !Log in to reply

– Shubham Dhull · 2 months, 2 weeks ago

thnx bro...... word like these give me some motivation (eve though i think the ditch in which i have fallen is too deep to come out of :(Log in to reply

now!Or else regret rest of your life!Consult your parents if needed.See you can come out of the dictch, since if you could not come out, then you might have not regretted.

But you are regretting and that's a positive sign and it means that you can recover back to your normal studies! :)

You just need to be in discipline for 1 week and then you will automatically be normal.

Its is never too late.

Be engaged in

fruitfulactivities all day.Thanks for reading this LONG post :P

Cheers!!

(I may sound an old teacher but i like to spread motivation, my freinds call me motivator baba :P) – Harsh Shrivastava · 2 months, 2 weeks ago

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– Harsh Shrivastava · 2 months, 2 weeks ago

That's your problem, you need to be strict on yourself.Log in to reply

– Prakhar Bindal · 2 months, 2 weeks ago

Tujhe maine kitni baar kaha hai ek test tera fait decide nahi kar sakta!Log in to reply

Please give some tips on how to solve paper?

Thanks! – Harsh Shrivastava · 2 months, 2 weeks ago

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For your question i would rather say solving chemistry and bio first (they wont consume more than 30 minutes). the two markers are also theoretical . either you know or you dont. its not a good idea to spend time on thinking biology questions if you dont know the solution.

Then i would say move to physics or maths (personal choice) . i did physics coz i knew that i was strong at maths and it will take my rank up .

I Finished physics in about 45 minutes (including 2 markers). i was left with 1 hour 45 minutes of which i devoted 1 hour 30 minutes to maths thinking twice checking each step . it was also fruitful i got a perfect score 25/25 in maths

Then in remaining 15 minutes i had a good look at the whole paper (made some intelligent guesses and 2-3 i did by tukabazi)

All the best! :) – Prakhar Bindal · 2 months, 2 weeks ago

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– Harsh Shrivastava · 2 months, 2 weeks ago

Thanks.Log in to reply

– Prakhar Bindal · 2 months, 2 weeks ago

i expect that you might have seen last year's paper. i honestly finished maths in 40 minutes (it was quite easy). just i checked my steps to avoid any silly errors!.Log in to reply

– Nihar Mahajan · 2 months, 2 weeks ago

Plz add me too 😅Log in to reply

– Harsh Shrivastava · 2 months, 2 weeks ago

I'll add you tmmrw k?Log in to reply

– Nihar Mahajan · 2 months, 2 weeks ago

Anytime before JEE 2018 (LOL)Log in to reply

– Shubham Dhull · 2 months, 2 weeks ago

where ?Log in to reply

– Harsh Shrivastava · 2 months, 2 weeks ago

Slack iitjee channelLog in to reply

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– Prakhar Bindal · 2 months, 2 weeks ago

Ye koi puchne wali baat nhi haiLog in to reply

– Shubham Dhull · 2 months, 2 weeks ago

arrre bata yaar add kar raha hai ya nahi ???Log in to reply

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– Aniket Sanghi · 2 months, 2 weeks ago

Check your InboxLog in to reply

– Shubham Dhull · 2 months, 2 weeks ago

got nothing !Log in to reply

– Prakhar Bindal · 2 months, 2 weeks ago

Ohk . i am also not there can you add me too?Log in to reply

– Harsh Shrivastava · 2 months, 2 weeks ago

kkLog in to reply

prakhar.bindal@ymail.com – Prakhar Bindal · 2 months, 2 weeks ago

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– Harsh Shrivastava · 2 months, 2 weeks ago

No i'll not add u :PLog in to reply

– Nihar Mahajan · 2 months, 2 weeks ago

.... Says the motivation baba ;PLog in to reply

– Aniket Sanghi · 2 months, 2 weeks ago

Which chat room are you talking about , the one I mentioned above?Log in to reply

– Harsh Shrivastava · 2 months, 2 weeks ago

Yes, when i click on join it says account disabled.Log in to reply

– Aniket Sanghi · 2 months, 2 weeks ago

Give me your emailLog in to reply

– Harsh Shrivastava · 2 months, 2 weeks ago

harshus99@gmail.comLog in to reply

– Aniket Sanghi · 2 months, 2 weeks ago

Check your emailLog in to reply

– Harsh Shrivastava · 2 months, 2 weeks ago

Thanks.Log in to reply

I am just plain regular math lover. Not much....😅 I am not preparing for the JEE, but would love to be the part of the discussion. ( I am an army cadet! )😁 – Rajbir Malik · 3 months ago

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Hi.😇 – Rajbir Malik · 3 months ago

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– Aniket Sanghi · 2 months, 2 weeks ago

Welcome ( Late response I know ! :P)Log in to reply

i want to invite the most intelligent person here but i hope he comes(he is not much active here!) : @Rajbir Malik – Shubham Dhull · 3 months ago

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– Harsh Shrivastava · 3 months ago

Who is he?Log in to reply

– Shubham Dhull · 3 months ago

the most intelligent person present here in our age group !Log in to reply

– Prakhar Bindal · 3 months ago

Who is he?? an olympiad medalist?Log in to reply

– Shubham Dhull · 3 months ago

nopeLog in to reply

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@Aniket Sanghi – Shubham Dhull · 3 months, 2 weeks ago

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@Aniket Sanghi – Shubham Dhull · 3 months, 2 weeks 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 · 3 months, 3 weeks ago

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– Aniket Sanghi · 3 months, 3 weeks ago

M/m = 4 v = (1/2)(gl/2)^0.5Log in to reply

– Shubham Dhull · 3 months, 3 weeks ago

why don't u come over slack ?Log in to reply

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Sry I didn't knew that this prob was already posted on b'llant. – Harsh Shrivastava · 3 months, 3 weeks ago

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– Shubham Dhull · 3 months, 3 weeks ago

can u give link to prob plzLog in to reply

– Aniket Sanghi · 3 months, 3 weeks ago

I can't do that ! As that would be cheating ;)Log in to reply

– Shubham Dhull · 3 months, 3 weeks ago

just the link?Log in to reply

– Aniket Sanghi · 3 months, 3 weeks ago

1st tell me , why do u want that?Log in to reply

– Shubham Dhull · 3 months, 3 weeks ago

to solve it myselfLog in to reply

Which Resnick Halliday is better? The one written exclusively for jee advanced or one which is not? – Harsh Shrivastava · 9 months ago

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– Akul Agrawal · 9 months ago

Best is Resnick Halliday Crane ( I will not suggest Walker neither do I criticise it).Log in to reply

– Aditya Kumar · 9 months ago

Go for the original one. That'll help you for NSEP+JEE.Log in to reply

Is this good? – Harsh Shrivastava · 9 months ago

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– Aditya Kumar · 9 months ago

I have Resnik Walker Hallinday. This is different. I have an old book. So I don't know about the new one.Log in to reply

If you have few mins to spare, can you please give me a review about your book? Thanks! – Harsh Shrivastava · 9 months ago

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– Aditya Kumar · 9 months ago

Yes it was useful only for theory. Good for clearing concepts.Log in to reply

– Harsh Shrivastava · 9 months ago

Ohk thanks! Clearing of concepts is what I need!Log in to reply

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 · 9 months ago

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– Aniket Sanghi · 9 months ago

1 st question : how many radial nodes are present in the orbital represented as : n = 5 , l = 2 , m = 0.Log in to reply

Number of angular nodes = l = 2

Total Nodes (Excluding the one at infinity) = 4

Total Nodes (Including Infinity one) = n = 5 – Prakhar Bindal · 9 months ago

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– Aryan Goyat · 9 months ago

dz2 has no nodal planes it has two nodal conical surface..Log in to reply

– Prakhar Bindal · 9 months ago

Can You Please elaborate? and can you tell from where can i learn these things about nodal planes,nodes etc?Log in to reply

– Aryan Goyat · 9 months ago

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/".Log in to reply

@aryan goyat @Mayank Singh – Aniket Sanghi · 9 months ago

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– Mayank Singh · 9 months ago

I've blackLog in to reply

– Aniket Sanghi · 9 months ago

Is that better than orange one? What's your analysisLog in to reply

– Mayank Singh · 9 months ago

never ceen the orangeLog in to reply

– Aryan Goyat · 9 months ago

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.Log in to reply

– Aniket Sanghi · 9 months ago

I want to be confined with jee syllabus and don't want to miss anything , then which one to preferLog in to reply

– Aryan Goyat · 9 months ago

orange one :)Log in to reply

– Aniket Sanghi · 9 months ago

And what's your expected score in jee mainLog in to reply

– Aryan Goyat · 9 months ago

i am in 12 now and will appear for jee in 2017.Log in to reply

– Prakhar Bindal · 9 months ago

I too have orange one :) For JEELog in to reply

And were you knowing aryan goyat is of our age (I thought he is 1 year ahead) – Aniket Sanghi · 9 months ago

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– Shubham Dhull · 4 months ago

it's the very basic of nodes , you can find it in the great " NCERT " textbook if you see it my bro.Log in to reply

– Aniket Sanghi · 9 months ago

Right! Can you elaborate about nodal conical suface (I would like to know)Log in to reply

– Aryan Goyat · 9 months ago

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.Log in to reply

– Aniket Sanghi · 9 months ago

Wrong answer!Log in to reply

– Prakhar Bindal · 9 months ago

But why?Log in to reply

– Aniket Sanghi · 9 months ago

I think you didn't try my set !Log in to reply

– Aryan Goyat · 9 months ago

you have asked here radial nodes which is n-l-1 may it be 5z2.Log in to reply

– Aniket Sanghi · 9 months ago

What 5z2Log in to reply

– Aryan Goyat · 9 months ago

its 5dz2 .Log in to reply

– Aniket Sanghi · 9 months ago

It is definetely 5dz2 as m =0 is for dz2Log in to reply

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

@Sandeep Bhardwaj – Aniket Sanghi · 9 months ago

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What is adv. – Arpan Manchanda · 9 months ago

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– Aniket Sanghi · 9 months ago

What are you asking?? Be clearLog in to reply

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 · 9 months ago

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– Saarthak Marathe · 9 months ago

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 \(2*2\pi*R\).Log in to reply

Is reading NCERT for inorganic enough? – Aditya Kumar · 9 months, 1 week ago

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– Mayank Singh · 9 months ago

JD LEE + NCERT + Your institute's notes + Previous years papers = total JEE advanced inorganic chemistryLog in to reply

– Aditya Kumar · 9 months ago

Thanks I was doing JD LEE now. I was not sure whether that level would come. Now I shall read it more seriously.Log in to reply

– Mayank Singh · 9 months ago

i dont think soLog in to reply

– Aniket Sanghi · 9 months ago

We are told that's enough for rest our fiitjee materials fill the vacant spacesLog in to reply

Nice – Mayank Singh · 9 months, 1 week ago

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– Mayank Singh · 9 months, 1 week ago

It would be called cheating if we post a solution to a brilliant problem here, moderators would delete itLog in to reply

– Gauri shankar Mishra · 9 months, 1 week ago

Sorry SirLog in to reply

@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 · 9 months, 1 week ago

Yes you are right.Log in to reply

– Gauri shankar Mishra · 9 months, 1 week ago

Sorry SirLog in to reply

How is your study going? – Rishabh Deep Singh · 9 months, 1 week ago

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@Gautam Sharma @Pranshu Gaba @Vighnesh Shenoy @Abhineet Nayyar @Akul Agrawal @Rishabh Deep Singh @Rishabh Cool @Surya Prakash – Aditya Kumar · 9 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 · 9 months, 1 week ago

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– Prakhar Bindal · 9 months, 1 week ago

Thats a nice InitiativeLog in to reply

– Gauri shankar Mishra · 9 months, 1 week ago

Great workLog in to reply

@Anshul Sanghi @ANSHUL SHRIVASTAVA @Harsh Shrivastava @Ashish R. Nair @Naman jain @Hargun Singh @Jyotisman Das – Aniket Sanghi · 9 months, 1 week ago

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@Kalash Verma @Nihar Mahajan – Harsh Shrivastava · 9 months, 1 week ago

@Adarsh KumarLog in to reply

@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 · 9 months, 1 week ago

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– Sandeep Bhardwaj · 9 months, 1 week ago

Sure. Always happy to help :)Log in to reply

@aryan goyat – Prakhar Bindal · 9 months, 1 week ago

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@Harsh Shrivastava . I Think we can talk here – Prakhar Bindal · 3 months, 2 weeks ago

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Wbu, top 50s? – Harsh Shrivastava · 3 months, 2 weeks ago

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– Prakhar Bindal · 3 months, 2 weeks ago

I Got 15 in ai^2ts 1 . but it does not matter . look at your mistakes and try to improve in nextLog in to reply

– Prakhar Bindal · 3 months, 2 weeks ago

Of class 11Log in to reply

Our next aiits is on 17th and RMO is on 16th, also cm test on 11th and kvpy on 6th novemeber, many exams ahead :p – Harsh Shrivastava · 3 months, 2 weeks ago

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– Prakhar Bindal · 3 months, 2 weeks ago

Ohh go ahead. KVPY Isn't a big deal but bio can trouble you a lot (i remember scoring about 7 marks out of 25 in aptitude test which was primarily responsible for not so good rank in KVPY)Log in to reply

– Harsh Shrivastava · 3 months, 2 weeks ago

Thanks.Log in to reply

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 · 4 months ago

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Its link is mentioned in this discussion start. – Aniket Sanghi · 4 months ago

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– Shubham Dhull · 4 months ago

i joined it but nothing happens at all .Log in to reply

I hope I don't disturb you when I ask my doubts? – Harsh Shrivastava · 4 months ago

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– Prakhar Bindal · 4 months ago

Nahh its my free time. i am watching Taarak MehtaLog in to reply

– Shubham Dhull · 4 months ago

if it's your free time bonus: prove the result i am using.Log in to reply

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 · 4 months ago

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– Shubham Dhull · 4 months ago

is'nt my method correct?Log in to reply

– Prakhar Bindal · 4 months ago

You are Using one result to prove another. He wants the proof of the result you are preassuming to be true!Log in to reply

dmv^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 · 4 months ago

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– Prakhar Bindal · 4 months ago

mv^2/6?Log in to reply

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

A physics problem. – Harsh Shrivastava · 4 months ago

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– Prakhar Bindal · 4 months ago

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 timeLog in to reply

– Harsh Shrivastava · 4 months ago

No prob :)Log in to reply

– Shubham Dhull · 4 months ago

i can help if you want !Log in to reply

I'll post the prob after 30 mins, havta go out. – Harsh Shrivastava · 4 months ago

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– Shubham Dhull · 4 months ago

i think i have waited much than you saidLog in to reply

– Harsh Shrivastava · 3 months, 3 weeks ago

Sorry bro, net was down.Log in to reply

– Shubham Dhull · 4 months ago

ok i'll be waiting uptill thenLog in to reply

– Harsh Shrivastava · 4 months ago

Correct! Please give a hint.Log in to reply

– Shubham Dhull · 4 months ago

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.Log in to reply

– Harsh Shrivastava · 4 months ago

Why is the contribution m/3?Log in to reply

– Shubham Dhull · 4 months ago

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 !Log in to reply

Can someone please post a solution to this problem . please!!!! – Gauri shankar Mishra · 8 months, 2 weeks ago

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try this https://brilliant.org/problems/no-story-this-time/?ref_id=1178336 – Mayank Singh · 9 months ago

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– Prakhar Bindal · 9 months ago

Again let it get some rating :PLog in to reply

– Aniket Sanghi · 9 months ago

without rating , dont we get the creditLog in to reply

– Mayank Singh · 9 months ago

u get 100 pointsLog in to reply

– Mayank Singh · 9 months ago

ok okLog in to reply

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 · 9 months ago

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@rohit kumar @Mayank Singh @aryan goyat @Akul Agrawal @Aniket Sanghi – Prakhar Bindal · 9 months ago

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– Akul Agrawal · 9 months ago

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).Log in to reply

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 · 9 months ago

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– Aniket Sanghi · 9 months ago

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)Log in to reply

– Prakhar Bindal · 9 months ago

What is relation between monotonicity and normals? . why will it have only one normal for x> 0 please explainLog in to reply

GraphClearly 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 · 9 months ago

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– Prakhar Bindal · 9 months ago

but x axis does not pass through (0,1)Log in to reply

@Akul Agrawal – Prakhar Bindal · 9 months ago

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Those who love chemistry are invited to try these (BEST OF JEE - ADVANCED) – Aniket Sanghi · 9 months 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 · 9 months ago

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– Aryan Goyat · 9 months ago

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)Log in to reply

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– Aryan Goyat · 9 months ago

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)Log in to reply

– Aniket Sanghi · 9 months ago

I thought you were 1 year ahead! Are you in fiitjeeLog in to reply

– Aryan Goyat · 9 months ago

yes fiitjee jaipur.Log in to reply

– Aniket Sanghi · 9 months ago

What's your AIITS Rank historyLog in to reply

– Aryan Goyat · 9 months ago

near 50s (average)Log in to reply

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– Aryan Goyat · 9 months ago

and your histroyLog in to reply

– Aniket Sanghi · 9 months ago

Top 20sLog in to reply

– Aryan Goyat · 9 months ago

please provide me the link of it.Log in to reply

– Prakhar Bindal · 9 months ago

https://www.quora.com/Why-is-hydrochloric-acid-stronger-than-sulphuric-acid-even-though-sulphuric-acid-should-dissociate-to-produce-more-hydrogen-ionsLog in to reply

– Prakhar Bindal · 9 months ago

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 wikipediaLog in to reply

– Prakhar Bindal · 9 months ago

That's the problem . I Looked up Wikipedia it says HCl which even confuses me moreLog in to reply

– Aniket Sanghi · 9 months ago

Wikipedia is not authentic ,it can be edited!Log in to reply

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 · 9 months ago

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– Prakhar Bindal · 9 months ago

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 solomonsLog in to reply

@aryan goyat – Pankaj Gupta · 9 months, 1 week ago

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– Pankaj Gupta · 9 months, 1 week ago

u there?Log in to reply

– Aryan Goyat · 9 months, 1 week ago

yesLog in to reply

– Pankaj Gupta · 9 months, 1 week ago

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?Log in to reply

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 · 9 months, 1 week ago

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– Pankaj Gupta · 9 months, 1 week ago

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 oneLog in to reply

– Aryan Goyat · 9 months, 1 week ago

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.Log in to reply

– Pankaj Gupta · 9 months, 1 week ago

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 actLog in to reply

– Aryan Goyat · 9 months, 1 week ago

next did you find any horizontal force which is making it out of rolling in time dt.Log in to reply

– Aryan Goyat · 9 months, 1 week ago

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.Log in to reply

– Pankaj Gupta · 9 months, 1 week ago

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 conceptLog in to reply

– Aryan Goyat · 9 months, 1 week ago

as much i know "no question is a silly question"Log in to reply

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 · 9 months ago

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– Aryan Goyat · 9 months ago

absolutely correct.Log in to reply

@aryan goyat because of you my rolling concept became clear – Pankaj Gupta · 9 months ago

Thanks a lotLog in to reply

– Aryan Goyat · 9 months ago

i told you earlier too no need of thanks.Log in to reply

– Prakhar Bindal · 9 months ago

Ab to tujhe samajh me aa gaya?Log in to reply

– Pankaj Gupta · 9 months ago

Yes i got it tujhe samjhana hi nahi aata :PLog in to reply

– Prakhar Bindal · 9 months ago

Maybe i am not good at explainingLog in to reply

– Aryan Goyat · 9 months, 1 week ago

not after first after second.Log in to reply

– Pankaj Gupta · 9 months, 1 week ago

Yeah i meant first collision with rough groundLog in to reply

– Aryan Goyat · 9 months, 1 week ago

sorry i did not noticed the phrase "rough surface" .Log in to reply

– Pankaj Gupta · 9 months, 1 week ago

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 surfaceLog in to reply

– Pankaj Gupta · 9 months, 1 week ago

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?Log in to reply