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Catalogs Discussion Forums -> General Knowledge -> kindly tell me wat minimum percentage of the omr circles should b darkened i have darkened only 70 -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
kindly tell me wat minimum percentage of the omr circles should b darkenedi have darkened only 70 - 80% in aieee as it was to b filled with black pen
Catalogs Discussion Forums -> Course Material -> i am getting 250 marks in jee 2011. what is my expected rank? - -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

hey dude congrats

i will suggest u to go to the official web site of FIITJEE

they have uploaded some " sucess check"

enter ur marks there and they will tell ur aprox rank

well wat were ur subject wise marks

feel free to ask mine

all the best

Catalogs Discussion Forums -> Trignometry -> prove sinx/x=1 at x aproches to "0" -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

u seem to be new and hence ur knowledge is not enough to prove it 2 u(if u r not testing all of us)

but there r 3 ways by which i can help u

go for these if they seem to b helpful

1st

graph method

if u know graphs of both the curves i.e. y=sinx and y=x

then u can see that y=x is tangent to y= sinx at x=0

hence both of them have very close values at x=0

2nd

series mthod

sinx is just not a function but it is a series

sinx= x  - x^3/3! + x^5/5!....

so sinx/x= 1-x^2/3! + x^4/5!

hence wen we apply lim x tends to zero, sinx / x= 1

3rd

if u know L hopitals rule then u can prove it urself

all the best

Catalogs Discussion Forums -> Algebra -> wat will be the remainder wen 4^87 is divided by 3 ?pls explain -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

see gal one person has already told one way to get to the ans easily

but for beginers i would sugest the folowing way

u hv got 4^87 / 3

= 4.4.4.    ..................4.4.4  87 times divided by 3

=4/3 4^86

=(1+ 1/3) 4^86

=4(1+1/3)4^85

=(4+4/3)4^85

=(4+1+1/3)4^85

=(5+1/3)4^85

=(20+4/3)4^84

=(21+1/3)4^84

...........................

..................

=(k+1/3) where k is a constant

hence remainder is 1

now try this one

its a bit tricky

5555^2222 + 2222^5555 when divided by seven gives remainder = ? ans is 0

Catalogs Discussion Forums -> Inorganic Chemistry -> does Ma3b3 complex show optical isomerism? if not then show the plane of symmetry -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
does Ma3b3 complex show optical isomerism?if not then show the plane of symmetry
Catalogs Discussion Forums -> Differential Calculus -> limit x---0 [ (x^2)/(tanx sinx)] where [ ] denotes greatest integer function. -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

hey cant we simply use the graphs

clearly limx-o sinx/x =1- ( say 1-h where h tends to 0) and also limx-0 tanx/x = 1+( say 1+h)

so we get int (1-h)/1+h = 0 [int is greatest integer function]

Catalogs Discussion Forums -> Mechanics -> A bit high level question. For very correct answer there will be 5 points. -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

hey friends i think that none of options given is correct.according to me collision will not take place if driver of car A anyhow reduces his speed to Vb within the distance s so s>= Vb^2 - Va^2/ 2a

Catalogs Discussion Forums -> Lounge -> Post the biggst lie! Any untinkable lie will be rated! lie -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

"it is a girl:s world"

Catalogs Discussion Forums -> Mechanics -> Suppose the earth suddenly stops attracting objects placd near its surface.A persn standng -> Go to message
This Post 2 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

remain standing

when earth stops attracting objects there is no other massive body which can provide net effective attractive force for the other objectsto cause their motion(acceleration)

Catalogs Discussion Forums -> General Physics -> a car leaves station x to y every 10 min. dist between the two station is 60 km. the car t -> Go to message
This Post 4 points    (Olaaa!! Perrrfect answer.   in 2 votes )   [?]

7 cars.

Catalogs Discussion Forums -> Inorganic Chemistry -> stochimetry -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

since whole of the MNO2 is finished so

according to the equivalent concept

n1 z1 = n2 z2 no of equivalents of MNO2 = no of equivalents of MNO3

 where z1 and z2 are the respective z factors or the n factors

10/molecular mass of MNO2 x 4 =w/molecular mass of MNO3 x 6

on solving we get w = 7.87 gms

Catalogs Discussion Forums -> Analytical Geometry -> Straight lines -> Go to message
This Post 2 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

i have checked that the answer posted by the forrumn expert and my answer is correct but i think i have an easier method

first substitute the vallue of y=3^1/2 x to get a byquadratic eqn in x as

x^4+ 3^1/2 a x^3 + 3^1/2 b x^2 + (3^1/2 d +c) x+6 = 0

now, the product of the roots of the equation x1 x2 x3 x4 = 6

distance of A from origin ( x1^2 + y1^2)^1/2 now, since x1, y1 lie on y = 3^1/2 x so y1 = 3^1/2 x1

this implies OA = (x1^2 +3 x1^2)^1/2= 2x1

similarly OB = 2 x2 OC = 2 x3 OD = 2 x4

so OA.OB.OC.OD = 16 x1 x2 x3 x4 =16 x 6 = 96

did you get it!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Catalogs Discussion Forums -> Analytical Geometry -> Straight lines -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

is the answer 96. if it is then tell me i will post the complete solution

Catalogs Discussion Forums -> Mechanics -> If T1 and T2 represent the respective time periods of oscillation of a and b, the correct relati -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

T2>T1 if the masses of the blocks and the spring constants are equal

u might have got the time period of the first block as T1 = 2 pie (m/k)^1/2

in second one if the block is pulled by x distance from the equilibrium position then the pulley will be displaced by x/2 distance as a result an upward force of  -kx/2 is experienced by the pulley. now the tension in the string joining pulley with spring is twice the tension in the string joining the block with the ground. so the force on the block

F = -kx/4

so time period of the second block T2 = 2 pie (4m/k)^1/2 T2 = 2pie x 2 (m/k)^1/2

so T2 = 2T1

Catalogs Discussion Forums -> Mechanics -> a thin ring of mass=4kg and radius 1m. find its moment of inertia about an axis passing through its -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

answer is 2 kg m^2

take the axis about which moment of inertia is to be found as one of the perpendicular axis and one axus perpndicular to it as another axis and treat them as the perpendicular axis and then apply perpendiculat axis theorem.another way of thinking is that the moment of inertia is dependant only on mass and distribution of mass about the axis which here is same for the axis along the centre in the plane of the ting and about the axis about which moment of inertia is to be found.................

Catalogs Discussion Forums -> Mechanics -> the period of oscillation of mass M suspended from a spring of neglecting mass is T. if along with a -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

the final time period will be root 2 times the initial time period that is

T- = root 2 T

for solution use t = 2 pie (m/k)^1/2

initially T = 2 pie (M/K)^1/2

now, final time period = 2 pie (2M/k)^1/2

as now the net deforming force is 2Mg = k x-

Tf = (2)^1/2 2 pie (M/k)^1/2

Tf = 2^1/2 Ti = 2^1/2 T

Catalogs Discussion Forums -> Thermal Physics -> two black metallic spheres of radius 4m at 2000K and 1m at 4000K will have ratio of energy radiation -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

since E=Pt where t is the time for emmisivity of radiant energy.so

E = sigma A absillion T^4 t

where sigma is stefan;s constant

A is the area for radiation

absillion is emissivity

this implies E1/E2 = sigma 4 pie 4^2 (2000)^4 t /sigma 4 pie 1^2 (4000)^4 t

E1/E2= 16x 1/16 = 1

Catalogs Discussion Forums -> Mechanics -> a particle performs SHM in a straight line.in the 1st second,starting frm rest is covers a distance -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

answer is c 2a^2/3a-b

take the equation of shm of the particle as x = A Cos wt-kx

now apply the given condition for the displacemen in first second

for diplacement in second second find total displacement in 2 secods and subtract it from the displacement in first second.

now, solve the obtained equations..........

u will get the answer yourself................

did u get it!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Catalogs Discussion Forums -> Thermal Physics -> An ideal gas having pressure P, volume V and temperature T is allowed to expand adiabatically until -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

according to adiabatic expansion,

PV^gamma = constant

using ideal gas equatio the above law can be reduced to

TV^gamma-1 = constant

now, applying the given conditions

T V^gamma-1 = T/2 [4 2^1/2 V]^gamma-1

this implies 2 = [2^5/2]^gamma-1

i.e. 2^1 = 2^(5/2(gamma-1))

this impies 1 = 5/2 (gamma-1)

on solving we get,

gamma = 7/5

equating gamma with 1+2/f, where f is the degree of freedom,

we get f = 5

Catalogs Discussion Forums -> Electricity -> a question on charges -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

q/4

 
 
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