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@Gyro Gearloose
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full qn
since there is some initial velocity in the second case
the amplitude will shift
I'm calculating the amplitude using energy conservation
but I'm not getting it right
@Arseph
how is this SHM?
assumption
tunnet thru earth wala
hain
mujhe smaj nhi aya ye question
tunnel*
arey tunnel thru earth wala nahi bataya kya?
nhi
maine nhi kiya hai
Answer is √Rg ?
yes
Ok
Do you know how to do the normal case without the initial velocity?
yessir
.
Ok so by that you get an equation for shm and in this case in case of wt just put wt+phi
And then you will get 2 equations one with satisfying the initial velocity and one for the position when it's at T/2
yeah I get that
Amplitude shouldn't change just phase will
but why am I getting incorrect amplitude using energy conse
no?
amplitude should change
w will be same
yup
amplitude has to change
since there is some velocity at x = R
hence amplitude is not x =R anymore
Uh then I got it by luck ig I will try again.
yeah root(rg) toh bhot jage aata hai
@hithav chale gaye kya?
Ok
Got it
lesgooo
I thought the T0 is the full time period
yeah its T/2
That was the mistake I was doing thats why I took so long
Yeah i gtk
It's just trigonometry
Wait for 2 min I will write it properly and send
what if you find A using energy?
energy conservatn
Should give you the same value
it doesnt
What did you use
pls do it once using energy
potential energy = GMm/x
cuz initially it is at R from earth so ik its value
and finally its away from earth surface so uniform sphere treated as point mass
cuz A > R
and potential energy at distance R = -GMm/R
No it's not happens only when it's A>>R when it's near the force vectors won't cancel out properly
I Made the same mistake in some of the score tests
but satellite motion me toh we consider naa
score 😭
hmm this could be a score level qn tho idk
You gave the 19th March one ?
26tard hu lol
but I know its shit ass hard
Not all of them
Some are easy
oh
But the last one I wrote was very bad
They took questions from Olympiads
I gave COEs in 11th
sad
COEs are easier
COE ?
centre of excellence
or national srg or super srg tests
Send your method once
You got into srg ? Nice
ok
.
why do they have it there
and not here 😭
where?
@hithav
in my branch
which branc
mumbai mei
what
mumbai me toh hona chsiye
exactly
SRG toh hai mumbai me hamare teachers gaye the padhane waha
srg ya coe
?
SRG toh hai mumbai me idk about COE
oh no im in aakash bruski not allen
oh lmao
sad
I don't understand what you have done for getting the value of phi
the phasor rotates by 2phi
cuz you need to get from x = -R to +R
Ok
Fine I get it now
noice
so whats wrong?
One error is that you have taken the reciprocal of A wrong
In the 7th line
And even if you corrected that you still wouldn't get the answer
sad
what shld it be?
I don't know there is something wrong in the phasor method ig i don't see any other thing which would give you an error
did you guys get the ans
Yeah
whats wrong w my method
hmm
.
ight ill just check them out
i just saw the question
ok
@hithav what should be the correct angle of phi to get ans?
wtf it should be -2
something is fishy
I told no you took the reciprocal wrong
Should be -1/2
-1/2 wherE?
Sin(phi) should be -1/2
Phi -pi/6
what shld be reciproval
Sin(phi) should be (u^2-2rg)/2rg
waht
Yeah see what you have done once
oh lmaooo
brain wasnt braining that time
Try to avoid those kinds of mistakes
They hurt the most
fr
I did those in the actual mains :sweaty:
💔
shit wrong emoji
🥀
correct now
brb have dinner
@727 dekha?
I just saw the sol I didn’t see your approach
pls check then
oh @hithav
I asked my teacher this qn today
and he says that the approach could be wrong
which approach ?
our approach
see uh basically
phasor wala ?
earth ke andar and earth ke bahar field is different
so we can't extend the phasor
oh
your method and the book's method is same
but that must be incorrect since it is done using extension of phasors
there is no other method ?
there is a rigerous one
the very basic method
integrate and derive everything for that specific case ?
yeah
that method is just incorrect cuz of differences in fields
after you get out of earth its suddenly a point charge
ok understood
integration you can use when you are at home having plenty of time in exam pressure i dont think you can do it
yeah, atleast you know it now
+solved @hithav
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