Dpp ( Daily Practice Problem )

Here I’ll be posting some hand picked question ( mostly of jee advanced level ) for jee aspirants.
Rules are as follows :-

  1. I’ll post a question and a time frame after which I’ll post the solution of that question .
  2. Before completion of that time limit aspirants are requested not to post the answer or the solution to those questions , if they have solved the given question then they can like the post in which that question was given , so as to let us know how many students were able to solve them .
  3. Aspirants are not supposed to post their solutions/answers , so be honest with yourself ,you aren’t supposed to post the answers quickly so instead of just getting the answer quickly you should rather practise and solve those questions properly. Even if you have seen some of the questions before , try and solve it , because the sole purpose of this thread is to provide you students some good questions .
  4. If after the solution is out some aspirant has got some other approach to solve the given question , they are free to post their alternative solutions !
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Time limit :- 10 PM

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Solution :-

Important:- Solve by 2 different methods !
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Time limit 9:30 AM

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Method 1
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Method 2

This methods teaches us that just by replacing x i + y j / root ( x² + y² ) with Unit vector along any point R vector can make this question much simpler !

In many more questions, this method helps us to reduce the solution to just one or two lines!

Part B of this problem is more important


Time limit -2 Pm

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Time Limit -6:00 Pm

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For the above question :-
Part a - find electric field
Part b - proving the charge distribution
Part c - finding electricity field using the knowledge that this charge distribution is actually distribution of charge when two spheres of opposite charge are kept very close

Prerequisite:-
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Very basic question
One or more than one options correct .
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Time limit :- 7:15 Pm

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Only option D is correct !
Option A also seems to be correct but it’s wrong
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Another method

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This is equivalent to taking a cylindrical symmetry instead of spherical symmetry.

Very simple question .

Number of resonating structures of
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Time limit -9:30 PM

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1)image
Time Limit-3PM

1 Like