Doubts from JEE PYQs

-OH is ortho para directing group then. One one ortho position ch3 is there and on the other ortho position steric hindrance will be there so only option is para… But in c option it is getting attached on meta position…how?!

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!

In the last line of the solution how did we get the expansion of ln term also is there any shortcut for this ques if we dont remember expansion

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This was in pg advanced illustration i guess u can refer that

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konsa?

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@Anorak https://youtu.be/hiuDMM8tckM

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thx dude

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An unknown metal of mass 192 g heated to a temperature
of 100°C was immersed into a brass calorimeter of mass
128 g containing 240 g of water at a temperature of 8.4°C.
Calculate the specific heat of the unknown metal if water
temperature stablizes at 21.5°C. (Specific heat of brass is
394 J kg–1 K–1) [10 Jan. 2019 II]
(a) 458 J kg–1 K–1 (b) 1232 J kg–1 K–1
(c) 916 J kg–1 K–1 (d) 654 J kg–1 K–1

Aisi calculations ko karna hi padega kya? Jaan nikal gayi meri iski calculations me…

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Hnn karna toh parega hi isme option hai toh approx lete chalna

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haan isme options spaced hh isliye approx se kaam chaalra hh :+1: :+1:

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Ek chhota doubt aur hai. @Deadpool

Kaise pata chalega ki newton’s law of cooling me average temp wala formula use karna hh ya integrated log(T- Ts) wala? Kabhi kisi se correct answer aata hh kabhi kisi se.

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here is my thinking process while approximately calculating

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Jab acche option ho(perfect integers or terminating decimal) tab average
i will confirm this after nitin sir completes this

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newtons law wale questions ka phrasing usually ek body vs room temperature par Hota hai and usually at equal intervals like 40C to 30C then 30C to 20C. yeh toh calorimetry hai seedhe seedhe

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A hot body, obeying Newton’s law of cooling is cooling
down from its peak value 80°C to an ambient temperature
of 30°C. It takes 5 minutes in cooling down from 80°C to
40°C. How much time will it take to cool down from 62°C to
32°C?

(a) 3.75 minutes (b) 8.6 minutes
(c) 9.6 minutes (d) 6.5 minutes

Isme average wale se 8 ke aas paas aa raha hh and integrated log wale se 6.5 and 6.5 is correct.

jab temp difference small ho

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between diff temperature or initial/final temp and room temp

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Fir yrr pata nahi confirm hojaye tab hi bolunga bikul risk nahi lene k

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Jab question me thori symmetry dikhti hh tab toh mai average wala freely use karta hu kabhi kabhi answer galat aata hh symm ke baad bhi …

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question dekhao ho sakta hai usme log use karna ho

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Jab nitin sir complete kare toh bata dena. maine toh 4th lecture ke baad se dekha nahi.

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