Congratulations for being selected to represent India in ijso.
Also what about JOMPC?
–
Shivam Jadhav
·
1 year, 4 months ago

Log in to reply

@Shivam Jadhav
–
rajdeep bhaiya online hai aur onhone ntse ke liye apply kiya tha
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Shivam Jadhav
–
Thanks. It will be out day after tomorrow. I have marked all the solutions I'll compile and post it on monday.
–
Rajdeep Dhingra
·
1 year, 4 months ago

@Rajdeep Dhingra
–
bhaiya aapne brilliant premium lifetime ke liye kitna pay kiya tha
–
Real Champ
·
2 months, 2 weeks ago

Log in to reply

nishant,ayushman,gaurang inme se kisine ntse clear kiya or aap school ke exams ke samay sirf school ka padte hai ya coaching ka bhi padte hai.
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

bhaiya mai ijso or ipho ke liye prepare kar raha ho toh mai kaise school ke saath use bhi padho or aapke 10 me kitne number thay
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

bhaiya yeh bata dijye ki school me jo course hai(icse) ka since i am in class 10 then how i can maintain a fine balance between academics and competitive study .
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

you are an ijso gold medalist or app to school ke bad coaching allen bhi jaate hai toh fir aap apna time kaise balance karte hai
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

BHAIYA IJSO KE LIYE KAUN SI BOOK SE PADHE AUR ASTRONOMY KE LIYE KISE PADHE
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

bhaiya pls reply
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

bhaiya physics olympiad ke liye kis book se theory padhe aur aapne ne ntse ke liye apply kiya tha
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

rajdeep u r of which coaching allen or fiitjee
–
Real Champ
·
3 months, 1 week ago

@Rajdeep Dhingra
–
you are an ijso gold medalist or app to school ke bad coaching allen bhi jaate hai toh fir aap apna time kaise balance karte hai or aap ne allen kis class mai join kiya tha
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Rajdeep Dhingra
–
pls help me bhaiya mai koi bhi nse ke paper ke liye kaise apply karo jab mera school register na ho toh since u r an ijso gold medalist u must have an idea about this question aur kya mai class 10 mai nsejs me apply kar sakta ho aapne kis class mai apply nsejs ke liye apply kiya tha.if u have any books then suggest me books for ijso and ipho
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Real Champ
–
I applied for NSEJS in class 9th. If your school isn't Registered , go to the nearest KV School and asked them to register you. For NSEJS simply do NCERT 9,10,11.(P,C,B). For maths practice past year papers or extra questions from NTSE type books.
–
Rajdeep Dhingra
·
2 months, 3 weeks ago

Log in to reply

@Rajdeep Dhingra
–
bhaiya mai ijso or ipho ke liye prepare kar raha ho toh mai kaise school ke saath use bhi padho or aapke 10 me kitne number thay
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Rajdeep Dhingra
–
nishant,ayushman,gaurang inme se kisine ntse clear kiya or aap school ke exams ke samay sirf school ka padte hai ya coaching ka bhi padte hai.
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Rajdeep Dhingra
–
i would like to share a simple problem with which u might have suffer.problem is that while preparing for ipho and ijso i am unable to study for boards and whenever i take leave from my school then i used to have scolds from principal of school .what is the average time an student should devote for preparing ipho and for application process in any foreign university like pennsylvania,california,mit.how u made a balance between ur school studies and competitive studies.u appeared for ntse or not.
–
Real Champ
·
2 months, 3 weeks ago

@Real Champ
–
i would like to share a simple problem with which u might have suffer.problem is that while preparing for ipho and ijso i am unable to study for boards and whenever i take leave from my school then i used to have scolds from principal of school .what is the average time an student should devote for preparing ipho and for application process in any foreign university like pennsylvania,california,mit.how u made a balance between ur school studies and competitive studies.u appeared for ntse or not.
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Real Champ
–
I did appear for NTSE , but couldn't make it to the next round as my SST is poor.
–
Rajdeep Dhingra
·
2 months, 3 weeks ago

Log in to reply

@Rajdeep Dhingra
–
similar will be the case with mine since my sst is poor and how to manage time or make a balance between academics and studies for ipho and ijso
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Rajdeep Dhingra
–
BHAIYA AAP KI ENGLISH TO KAAFI ACHI AUR ACCURATE HAI AAP TOEFL KE LIYE PRACTICE KAR RAHE HAI KYA
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Rajdeep Dhingra
–
BHAIYA CORSERA.ORG IS A VERY GOOD WEBSITE BUT HOW TO LEARN FROM IT
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Rajdeep Dhingra
–
BHAIYA AAPNE IJSO AUR IPHO ALONG WITH BOARDS KE LIYE KAISE TIME MANAGEMENT KIYA
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

@Real Champ
–
can u share ur phone number with me as or any mailid on google or yahoo as i ahve a lot of queries regarding nse's exams and how u study from coursera.org
–
Real Champ
·
2 months, 3 weeks ago

Log in to reply

Which book is it?
–
Ritik Gandhi
·
7 months, 2 weeks ago

Log in to reply

@Ritik Gandhi
–
I answered it before also , an old JEE subjective book. Just Mechanics for JEE is written on the book , nothing else.
–
Rajdeep Dhingra
·
7 months, 2 weeks ago

@Rajdeep Dhingra
–
And what about the above book(the one from which you sent questions?
Any clue through which I might be able to access the book?
–
Rasty Rocky Yoyo
·
4 months, 1 week ago

Log in to reply

@Rasty Rocky Yoyo
–
I think new Editions of it has been published by balaji publications. JEE Mechanics or something like that.
–
Rajdeep Dhingra
·
4 months, 1 week ago

Bro is your second doubt cleared ? i am getting it's answer as root 5g/7(R-r) tell if not cleared i will give the solution ( if my answer is correct.) .
–
Brilliant Member
·
1 year, 1 month ago

Hy rajdeep, can u give some tips for prepartion of nsejs , as my brother will be giving this year, presently he is in class 9.
–
Rahul Bubna
·
1 year, 3 months ago

Log in to reply

@Rahul Bubna
–
Read 9th and 10th class NCERT books thoroughly , if possible read 11th and 12th class NCERT also.(only relevant topics). For NSEJS most important is your speed of solving questions.
–
Rajdeep Dhingra
·
1 year, 3 months ago

Log in to reply

@Rajdeep Dhingra
–
If he starts from June 10 , is he will be able to clear nsejs ? He also goes to coaching ...
–
Rahul Bubna
·
1 year, 3 months ago

Question 2:
Let \( f \)denote the friction force acting on the body. Now, ablut the center of mass writing the torque equation,
\( f \cdot r = \dfrac{MR^{2}\alpha}{2} \)
\( f = \dfrac{MR\alpha}{2} \)
But since the cylinder doesn't slip \( r \alpha = a_{cm} \)
\( f = \dfrac{ma_{cm}}{2} \)
Now,
\( mg\sin(\theta) - f = ma_{cm} \)
\( mg\sin(\theta) = \dfrac{3ma_{cm}}{2} \)
\( a_{cm} = \dfrac{2g\sin(\theta)}{3} \)
\( \alpha = \dfrac{2g \sin(\theta)}{3r} \)
For small values of \( \theta \), \( \sin(\theta) \approx \theta \)
\( \alpha = - \dfrac{2g \theta}{3r} \)
The negative sign just denotes that direction of alpha is opposite to displacement.
This is the rotational analogue of \( a = -\omega^{2}x \)
\( \therefore \omega = \sqrt{\dfrac{2g}{3r}} \)
Frequency \( \dfrac{\omega}{2\pi} = \dfrac{1}{2\pi} \sqrt{\dfrac{2g}{3r}} \)
–
Vighnesh Shenoy
·
1 year, 4 months ago

Log in to reply

@Vighnesh Shenoy
–
It is wrong bro. \( \theta\) is the angle you moved the center of mass not the angle by which you rotated the sphere. Hence you can't equate \( {\omega}^2 \) to \(\dfrac{2g}{3r}\).
–
Rajdeep Dhingra
·
1 year, 2 months ago

## Comments

Sort by:

TopNewestCongratulations for being selected to represent India in ijso. Also what about JOMPC? – Shivam Jadhav · 1 year, 4 months ago

Log in to reply

– Real Champ · 2 months, 3 weeks ago

rajdeep bhaiya online hai aur onhone ntse ke liye apply kiya thaLog in to reply

– Rajdeep Dhingra · 1 year, 4 months ago

Thanks. It will be out day after tomorrow. I have marked all the solutions I'll compile and post it on monday.Log in to reply

– Ritik Gandhi · 5 months, 1 week ago

?????Log in to reply

– Rajdeep Dhingra · 5 months, 1 week ago

JOMC was a contest , I had to take out the result.Log in to reply

– Real Champ · 2 months, 2 weeks ago

bhaiya aapne brilliant premium lifetime ke liye kitna pay kiya thaLog in to reply

nishant,ayushman,gaurang inme se kisine ntse clear kiya or aap school ke exams ke samay sirf school ka padte hai ya coaching ka bhi padte hai. – Real Champ · 2 months, 3 weeks ago

Log in to reply

bhaiya mai ijso or ipho ke liye prepare kar raha ho toh mai kaise school ke saath use bhi padho or aapke 10 me kitne number thay – Real Champ · 2 months, 3 weeks ago

Log in to reply

bhaiya yeh bata dijye ki school me jo course hai(icse) ka since i am in class 10 then how i can maintain a fine balance between academics and competitive study . – Real Champ · 2 months, 3 weeks ago

Log in to reply

you are an ijso gold medalist or app to school ke bad coaching allen bhi jaate hai toh fir aap apna time kaise balance karte hai – Real Champ · 2 months, 3 weeks ago

Log in to reply

BHAIYA IJSO KE LIYE KAUN SI BOOK SE PADHE AUR ASTRONOMY KE LIYE KISE PADHE – Real Champ · 2 months, 3 weeks ago

Log in to reply

bhaiya pls reply – Real Champ · 2 months, 3 weeks ago

Log in to reply

bhaiya physics olympiad ke liye kis book se theory padhe aur aapne ne ntse ke liye apply kiya tha – Real Champ · 2 months, 3 weeks ago

Log in to reply

rajdeep u r of which coaching allen or fiitjee – Real Champ · 3 months, 1 week ago

Log in to reply

– Rajdeep Dhingra · 3 months ago

I was first in fiitjee , now in allen.Log in to reply

– Real Champ · 2 months, 3 weeks ago

you are an ijso gold medalist or app to school ke bad coaching allen bhi jaate hai toh fir aap apna time kaise balance karte hai or aap ne allen kis class mai join kiya thaLog in to reply

– Real Champ · 2 months, 3 weeks ago

pls help me bhaiya mai koi bhi nse ke paper ke liye kaise apply karo jab mera school register na ho toh since u r an ijso gold medalist u must have an idea about this question aur kya mai class 10 mai nsejs me apply kar sakta ho aapne kis class mai apply nsejs ke liye apply kiya tha.if u have any books then suggest me books for ijso and iphoLog in to reply

– Rajdeep Dhingra · 2 months, 3 weeks ago

I applied for NSEJS in class 9th. If your school isn't Registered , go to the nearest KV School and asked them to register you. For NSEJS simply do NCERT 9,10,11.(P,C,B). For maths practice past year papers or extra questions from NTSE type books.Log in to reply

– Real Champ · 2 months, 3 weeks ago

bhaiya mai ijso or ipho ke liye prepare kar raha ho toh mai kaise school ke saath use bhi padho or aapke 10 me kitne number thayLog in to reply

– Real Champ · 2 months, 3 weeks ago

nishant,ayushman,gaurang inme se kisine ntse clear kiya or aap school ke exams ke samay sirf school ka padte hai ya coaching ka bhi padte hai.Log in to reply

– Real Champ · 2 months, 3 weeks ago

i would like to share a simple problem with which u might have suffer.problem is that while preparing for ipho and ijso i am unable to study for boards and whenever i take leave from my school then i used to have scolds from principal of school .what is the average time an student should devote for preparing ipho and for application process in any foreign university like pennsylvania,california,mit.how u made a balance between ur school studies and competitive studies.u appeared for ntse or not.Log in to reply

– Real Champ · 2 months, 3 weeks ago

pls replyLog in to reply

– Real Champ · 2 months, 3 weeks ago

bhaiya aapne brilliant.org pe register ke liye kitne rupaye pay kiyeLog in to reply

– Real Champ · 2 months, 3 weeks ago

bhaiya can u suggest me books for ijsoLog in to reply

– Real Champ · 2 months, 3 weeks ago

i would like to share a simple problem with which u might have suffer.problem is that while preparing for ipho and ijso i am unable to study for boards and whenever i take leave from my school then i used to have scolds from principal of school .what is the average time an student should devote for preparing ipho and for application process in any foreign university like pennsylvania,california,mit.how u made a balance between ur school studies and competitive studies.u appeared for ntse or not.Log in to reply

– Rajdeep Dhingra · 2 months, 3 weeks ago

I did appear for NTSE , but couldn't make it to the next round as my SST is poor.Log in to reply

– Real Champ · 2 months, 3 weeks ago

similar will be the case with mine since my sst is poor and how to manage time or make a balance between academics and studies for ipho and ijsoLog in to reply

– Real Champ · 2 months, 3 weeks ago

BHAIYA AAP KI ENGLISH TO KAAFI ACHI AUR ACCURATE HAI AAP TOEFL KE LIYE PRACTICE KAR RAHE HAI KYALog in to reply

– Real Champ · 2 months, 3 weeks ago

BHAIYA CORSERA.ORG IS A VERY GOOD WEBSITE BUT HOW TO LEARN FROM ITLog in to reply

– Real Champ · 2 months, 3 weeks ago

BHAIYA AAPNE IJSO AUR IPHO ALONG WITH BOARDS KE LIYE KAISE TIME MANAGEMENT KIYALog in to reply

– Real Champ · 2 months, 3 weeks ago

can u share ur phone number with me as or any mailid on google or yahoo as i ahve a lot of queries regarding nse's exams and how u study from coursera.orgLog in to reply

Which book is it? – Ritik Gandhi · 7 months, 2 weeks ago

Log in to reply

– Rajdeep Dhingra · 7 months, 2 weeks ago

I answered it before also , an old JEE subjective book. Just Mechanics for JEE is written on the book , nothing else.Log in to reply

– Rasty Rocky Yoyo · 4 months, 2 weeks ago

hi rajdeep bhaiya which all books do u refer for physics olympiad?Log in to reply

– Rajdeep Dhingra · 4 months, 1 week ago

Irodov , Past Papers , Arvind Tiwari's Book for practice and Cengage for theory.Log in to reply

– Rasty Rocky Yoyo · 4 months, 1 week ago

how is krotov?Log in to reply

– Rajdeep Dhingra · 4 months, 1 week ago

It is good , like irodov only , but I haven't done it much.Log in to reply

– Rasty Rocky Yoyo · 4 months, 1 week ago

And what about the above book(the one from which you sent questions? Any clue through which I might be able to access the book?Log in to reply

– Rajdeep Dhingra · 4 months, 1 week ago

I think new Editions of it has been published by balaji publications. JEE Mechanics or something like that.Log in to reply

– Rasty Rocky Yoyo · 4 months, 1 week ago

Can you please reply?Log in to reply

– Ritik Gandhi · 5 months, 1 week ago

who's the author of the book?Log in to reply

– Rajdeep Dhingra · 5 months, 1 week ago

I don't know.Log in to reply

– Ritik Gandhi · 5 months, 1 week ago

publication?Log in to reply

– Rajdeep Dhingra · 5 months, 1 week ago

BalajiLog in to reply

– Ritik Gandhi · 5 months, 1 week ago

Ok thank you! Can you please send a pic of the cover page?Log in to reply

– Rajdeep Dhingra · 5 months, 1 week ago

I don't have the cover page , It is torn. Even the 1st Chapter is missing.Log in to reply

– Ritik Gandhi · 7 months, 2 weeks ago

who's the author of the book?Log in to reply

– Ritik Gandhi · 7 months ago

??Log in to reply

Bro is your second doubt cleared ? i am getting it's answer as root 5g/7(R-r) tell if not cleared i will give the solution ( if my answer is correct.) . – Brilliant Member · 1 year, 1 month ago

Log in to reply

– Rajdeep Dhingra · 1 year, 1 month ago

Cleared. Thanks anyways. P.S : your answer is correct.Log in to reply

Hey @Rajdeep Dhingra why not coming to fiitjee ? PLease tell the truth !! – Parth Bhardwaj · 1 year, 1 month ago

Log in to reply

– Real Champ · 3 months, 1 week ago

rajdeep u are of which coaching allen or fiitjeeLog in to reply

Which book is it ? – John Verghese · 1 year, 3 months ago

Log in to reply

– Rajdeep Dhingra · 1 year, 3 months ago

I don't know. Some old book for JEE subjective.Log in to reply

Hy rajdeep, can u give some tips for prepartion of nsejs , as my brother will be giving this year, presently he is in class 9. – Rahul Bubna · 1 year, 3 months ago

Log in to reply

– Rajdeep Dhingra · 1 year, 3 months ago

Read 9th and 10th class NCERT books thoroughly , if possible read 11th and 12th class NCERT also.(only relevant topics). For NSEJS most important is your speed of solving questions.Log in to reply

– Rahul Bubna · 1 year, 3 months ago

If he starts from June 10 , is he will be able to clear nsejs ? He also goes to coaching ...Log in to reply

– Rajdeep Dhingra · 1 year, 3 months ago

I think so.Log in to reply

Question 2:

Let \( f \)denote the friction force acting on the body. Now, ablut the center of mass writing the torque equation,

\( f \cdot r = \dfrac{MR^{2}\alpha}{2} \)

\( f = \dfrac{MR\alpha}{2} \)

But since the cylinder doesn't slip \( r \alpha = a_{cm} \)

\( f = \dfrac{ma_{cm}}{2} \) Now,

\( mg\sin(\theta) - f = ma_{cm} \)

\( mg\sin(\theta) = \dfrac{3ma_{cm}}{2} \)

\( a_{cm} = \dfrac{2g\sin(\theta)}{3} \)

\( \alpha = \dfrac{2g \sin(\theta)}{3r} \)

For small values of \( \theta \), \( \sin(\theta) \approx \theta \)

\( \alpha = - \dfrac{2g \theta}{3r} \)

The negative sign just denotes that direction of alpha is opposite to displacement.

This is the rotational analogue of \( a = -\omega^{2}x \)

\( \therefore \omega = \sqrt{\dfrac{2g}{3r}} \)

Frequency \( \dfrac{\omega}{2\pi} = \dfrac{1}{2\pi} \sqrt{\dfrac{2g}{3r}} \) – Vighnesh Shenoy · 1 year, 4 months ago

Log in to reply

– Rajdeep Dhingra · 1 year, 2 months ago

It is wrong bro. \( \theta\) is the angle you moved the center of mass not the angle by which you rotated the sphere. Hence you can't equate \( {\omega}^2 \) to \(\dfrac{2g}{3r}\).Log in to reply

– Brilliant Member · 10 months, 1 week ago

it would be 5g/7r instead !Log in to reply

– Rajdeep Dhingra · 1 year, 4 months ago

ThanksLog in to reply

@aryan goyat@Prakhar Bindal@Archit Agrawal@Aniket Sanghi Please help – Rajdeep Dhingra · 1 year, 4 months ago

Log in to reply

Solution for Question 1:Log in to reply

– Rajdeep Dhingra · 1 year, 4 months ago

Thanks !Log in to reply

– Saarthak Marathe · 1 year, 4 months ago

You are welcomeLog in to reply