Messages posted by hr

i think the ans can be any one of them... it has to return to the same phase... doesn't matter which phase and i didnt get how the others are crossed thrice or four times in a single oscillsation!

u obv assume that the oscillation begins from that particular phase...

so acc to me the ans shud be a,b,c as well as d.!

plz explain y i am wrong since all of u are rooting for option b..

thnx..

wads the ans?

hey for the first one... the torque is nt balanced once u pull the pan down... the arm of the balance is no longer perpendicular to the dirn of mg of the blck masses...
il get back to u on the 2nd...
acc to me i think u can say that for the 3rd... i agree with it... plz pose arguments against it if u dont agree...
thnx.
:)

hey... if the wire is infinite, its nt goin to have an end... thats the pt of an infinite wire.....! :):)
neway the elestric field is is radially outwards begining from the wire assuming it to be +vely charged else its radially inward...
the magnitude is :
2k.lambda / r
where lambda is the linear charge density of the wire and r is the radial distance from the wire at which u want to calculate the e. field...
can be gt by basic integration...
teme if i got it rite,
thx.
:):)

conserve linear momentum..cz ext force acting on the body is 0.....
simple!
:):):)

hey trisha... the mass on the right will be closer to the ground... whats the ans acc to u?
:):)
reply jaldi...
thx.

so true.... so true....
hmmm.... the irony...! very nice....
:):)

hey how are u supposed to calculate the ht reached by the the body if initial velocity isn't given??? if u assume the initial vel to be 0, the qn loses its sense...!

then obv the distance will be 0 coz the body wouldn't have moved at all..!!!

nd are u sure its distance and not displacement?

plz reply.....

hey nupur...

isn't the ans cos^-1(2/3)

if it is then u use the fact that normal rxn b/w particle n sphere becomes zero and the 2nd eqn will be that of conservation of energy.

two eqns, two unknowns, solve it!

if thats not the ans then it let me kno plz..

thx.

hey goutham, jus figured ti out myself... nd landed up with the same concl as u....... thx agn!

i assume the bananas wer at a ht.. i copied out wad the book sed...

neway wad u say makes perf sense to me...

got ur ans to the 2nd part.. bt the first part is unclear....

thanx neway...!

heyy... this is a very basic qn... bt m thoroughly confused..!!!

here goes...

a 20kg monkey has a firm hold on a light rope that passes over a frictionless pulley and is attached to a 20kg bunch of bananas...

the monkey looks up, sees the bananas and starts to climb towards them.

1. as the monkey climbs towards the bananas, do the bananas move, up, down or remain where they are?

2. what happens to the distance b/w the monkeys and the bananas? does it increase, decrease or remain constant?

the ans given by th text bk:

1. move up

2. constant.

plz giv me the reason for ur ans.....

thanx!!!

first of all.. nuthin "oh no!" abt circular motion...

second umang is completely right and therefore so is andy...

there are two accelerations-

1. tangential acc.

2. centripetal acc.

if the radius of the circle changes then u might have radial accn also... but dont complicate things..

the resultant acc. is the vector sum of the two acc mentioned above..

one component is along the tangent... [as u can deduce from the name itself!!]

reply and rate pls...

thanx.

heyy...usually in keto-enol tautomerism, compound usually exists in keto form which is more stable, UNLESS the enol form is aromatic.

the aromatic configuration stability>> non-aromatic configuration.

in such cases, if the enol is aromatic, then the compound exists 99%in that form... it cannot be 100% enol...no compund exists 100% as enol.... but 99 is really close...

m quite sure of my ans...

but if u find something wrong with it plz let me kno..

thx.

the ionic product has to be greater than the solubilty product for precipitaion to occur...

rajat and tarun are rite.

hey wickies.... u sed normal force doesnt depend on ne onther force... how can u say that??? dun agree...

for eg.

in a typical block on an incline problem.. the mormal rxn is usally mgcos

here normal rxn depends on weight na...?

plz make ur point clear to me

thx.

hey ash.. that's a gud sum.. requires a bit of attention.

here's my ans...

draw the FBD diagram for both blocks M n m.

N2-------- reaction force b/w M n m.

N1--------- reaction force b/w ground n M.

T------------ tension in string.

a1---------- acc of M in X dirn.

a2----------- acc of m in Y dirn.

Eqns for M in Y dirn:

1 .N2 +Mg + T = N1

Eqn for M in X dirn:

2T - N2 -

2.N1 = M.a1

Eqn for m in y dirn:

mg - T -

1.N2 = m.a2

Eqn for m in X dirn:

N2 = m.a1 . . . . . . [since M n m will have same acc in X direction]

constraint relation:

using

T.a = 0;

2T.a1 + T.a2 = 0;................ [ dot product of tension and acc]

2T x a1 + T x a2 x (-1) = 0;

2a1 = a2.

u now hav 5 eqns and 5 unknowns... solve the eqns for the required ans....

hope that suffices..

plz reply and rate...

thanx

heyy... the VMCA rule posted by arvind is the easiest and themost useful... though for sum compunds (most nitrogen cmpds) the VMCA rule fails...

for that the method given by rebel will help...

actually the VMCA has been derived from that only...get a teacher to explain it to u properly... its imp nd u shudn't get messed up by our answers.!!

Fate may know no master,

Destiny may remain free,

and whats written in the stars may eventually come to be,

but the human soul is wondrous,

with miracles more than few,

so whatevers willed to happen will inevitably come true...

so will for the deepest wish with all ur heart and it will be fulfilled....!

nice... very nice... and true...

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