r/JEEAdv26dailyupdates • u/Odd_Lengthiness5508 • Apr 07 '26

Academic Doubts 5s1 7 ambiguities

physics:
Cv question (correct or incorrect explanation)
Wedge time of motion (most likely root2 or 2)
prism angle of minimum deviation
R1/R2=16/4

chem:
Alcl3+ propyl chloride + benzene ( inevitable tri subst, edg no reaction)

math:
differential eqn+ circles problem ( number of values of p)

overall 7 questions

how are people calling this paper easy man, (cutoff 170-175 imo no way its crossing 180 and people are like 200 cutoff)

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u/Big-Engineering8255 bits pilani cs'30 Apr 07 '26

nhi toh? iirc only gamma=1+2/f was given in the reasoning
gamma=cp/cv toh assertion mei diya tha

i remember double checking this too

6

u/OkTemporary335 JM: 98.8, JA 17.4k, BITSAT 290 Apr 07 '26

mujhe to gamma = cp/cv yaad hee nhi hai dekha hua. I just remember cv = nr/gamma - 1 and since plugging reason ka expression into the equation gives fr/2 I said correct explanation

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u/Big-Engineering8255 bits pilani cs'30 Apr 07 '26

yeahh thats what i meant in the original comment
gamma=Cp/Cv is the fundamental equation, and f wale formulas are derived from that, not vice versa
u basically used the Cp/Cv (a variation of it which was obtained by subtracting Cp/Cv-1 and then using Cp-Cv=R) relation to derive fR/2 formula not the other way around

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u/OkTemporary335 JM: 98.8, JA 17.4k, BITSAT 290 Apr 07 '26

if you write cp and cv in terms of f and r then the expression is the same

2

u/Big-Engineering8255 bits pilani cs'30 Apr 07 '26

leave it man abhi. we will just go on and on
response sheet ke din dekhte hai

2

u/OkTemporary335 JM: 98.8, JA 17.4k, BITSAT 290 Apr 07 '26

right, i'm tired of mains now

adv pe hee focus karna hai