sign up I login
 advanced
refer a friend - earn nickels!!
sahilgupta_iit   sahilgupta_iit is offline sahilgupta_iit's messages in the community
Message
Catalogs Discussion Forums -> Algebra -> Determinants -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
1 replies   

Without expanding prove that det    =  (1 + a2 + b2)3

Catalogs Discussion Forums -> Differential Calculus -> Tangents and Normals: Part 2 -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
2 replies   

Q.1. Find the equation of line which is tangent at one point and normal at another ponit of the curve y = 8t3- 1, x = 4t2 + 3.


Q.2.  Find the minimum value of (x1 - x2)2 +( x12/4 - (16 - (x2 - 12)2)1/2 , x1R, x2[8,16].

Catalogs Discussion Forums -> Differential Calculus -> Tangents and Normals -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
3 replies   

Q.1. If the normal to the curve y=f(x) at x=0 can be given by the equation 3x-y+3=0, then find the value of  x2[(f(x2) - 5f(4x2) + 4f(7x2)]-1.


Q.2. If the tangent at any point of the curve x2/3 + y2/3 = a2/3 meets the axes of the coordinates in A and B then show that the locus of the mid-point of AB is a circle.


Q.3. If the curve x = a(cost + log(tan(t/2))), y = asint, show that the portion of the tangent between the point of contactb and the x-axis is of constant length.

Catalogs Discussion Forums -> Physical Chemistry -> What is acid rain? -> Go to message
This Post 2 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]
2 replies   
when fuels are burnt gases like NO2 and SO2 are released and go in the atmosphere. they combine with water vapours to form HNO3 and H2SO3 which come to the surface with the rain. this causes damages to buildings and also affects the plants
Community shelf Community shelf -> Summation of Series -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
4 replies   
mind-blowing sir
Catalogs Discussion Forums -> About IITs and JEE -> Is IIT jee2009 become objective & minimum percent is 75% in 12th -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
25 replies   
last saturday it was declared that JEE is on 12/04/2009 and of objective pattern
Catalogs Discussion Forums -> Magnetism -> Comprehension Passage -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
5 replies   
nobody to answer?
Catalogs Discussion Forums -> Optics -> ARE 15 DAYS ENOUGH FOR PREPARING BOTH GEOMETRICAL N WAVE OPTICS -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
2 replies   

you are asking about 15 days? i did it in a single day for my school exam. 15 days are more than enough to prepare a topic provided you are consistent. what i think is that you are giving too much time for these topics.


 

Catalogs Discussion Forums -> Organic Chemistry -> Which is correct order of SN1 reactivity???????? -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]
4 replies   
rate of SN1 reactions depend on the stability of the intermediate carbocation formed. so the order would be benzylic > allylic > 3 > 2 > 1 > methyl
Catalogs Discussion Forums -> Magnetism -> Comprehension Passage -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
5 replies   

mam,  this is a comprehension passage on which these five questions were based. how can i post these questions on different posts?

Catalogs Discussion Forums -> Magnetism -> Comprehension Passage -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
5 replies   

Totally Challanging questions.

Questions 1-5

  Particle storage rings faciliate collisions b/w elctronns and positrons (positively charged electrons). When electrons and positrons collide at high energies, they can annihilate each other and produce a variety of elementary particles, including photons. In these reactions, momentum is always conserved. Powerful magents are placed at various points along the ring to create a force directed towards the centre, thereby guiding the paticles in a circular motion. In a scattering exp., the particle beams circle in opposite directions and collide head-on at the intersection points, which are surrounded by particle detectors. The particles in the ring are acceletrated, they radiate electromagnetic energy. Radio frequecy power is continually fed into the storage ring to compensate for the energy loss.

  The reaction rate, R is the no. of particle scattered per second in the storage ring. It is given by the formula: R + L, where L is the luminousity and is the cross-section of the rewaction. The cross-section is a quantity that depends only on the particular type of reaction being considered. The luminousity contains all of the information about the initial conditions for a reaction and is given by:

                                   L = (Ne-Ne+)f / A

where Ne- refers to the no. of electrons, Ne+ referes to the no. of positrons, A is the cross-sectional area of the storage ring, and f is the no. of revolutions per second made by the particles. Electron-positron reaction rates for modern particle storage rings are typically on the order of 10-3 s-1.


 Q.1. What percentage of the wotk done on the circulating paticles is done by the magnetic field?

(a) 0%, because the direction of the magnetic froce is perpendicular to the direction in which the particles travel.

(b) 0%, because the magentic foeld doesn't exert a force on the particles.

(c) 50%, because the magenetic and electric field provide equal amounts to the paricles.

(d) 100%, because the magnetic field is the source for the centripetal force that accelerates the particles.


Q.2. Which of the following would increase the reaction rate in an electron-positron storage ring?

 (I) Decreasing the cross-sectional area of the storage ring

 (II) Increasing the energy of the particles

 (III) Increasing the no. of positrons in the storage ring.

(a) I only                            (b) III only                              (c) II and III only                                 (d) I, II and III


Q.3. The work done on the particles by the gravitational field of the earth is not considered when figuring their energy loss per revolution. This is because

(a) the gravitationl force is perpendicular to the gravitational ecceleration

(b) the energy lost is due to gravity is equal to the energy gained from the magnetic fields

(c) the particles do not experience a sigmificant gravitational force

(d) the luminosity is not dependant on gravitational acceleration


Q.4. Two electrons with equal speed collide head-on at the total energuy of 180 GeV. If the speed of the first electron after the collision is 0.9c, what is the speed of the second electron after collision ( c = 3 x 108 ms-1is the speed of light)

(a) 0.45c                              (b) 0.7c                           (c) 0.8c                               (d) 0.9c


Q.5. An electron and positron are held in a storage ring, and they each lose 260 MeV of energy per revolution in the form of electromagnetic radiation. If the frequency of revolution is 10,000 Hz, how much power must be supplied to keep the total energy constant at 180 GeV?

 (a) 1.8 x 106 MeV/s                                                                       

 (b) 2.6 x 106 MeV/s

 (c) 5.2 x 106 MeV/s

 (d) 9 x 108 MeV/s


Please explain the answer with solution. Rates assured...

Catalogs Discussion Forums -> Organic Chemistry -> Are these structures correct????????/ -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
6 replies   
i think there will be a single bond b/w I-I instead of a double bond
Catalogs Discussion Forums -> Organic Chemistry -> Is this mechanism to convert "Benzene to 4-bromo nitrobenzene" correct? -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
6 replies   
you must first do friedal craft halogenation followed by nitration. Br is o,p-directing group
Catalogs Discussion Forums -> Optics -> what is tir -> Go to message
This Post 2 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]
3 replies   
It stands for Total Internal Reflection. It happens when the angle of incidence equals or exceeds the Critical angle when ray of light gets refracted at surface of two media (first one is optically denser than the other). the right instead of passing through the other medium gets reflects back in the same medium. Critical angle is the angle for wich the angle of refraction is 90 degrees
Community shelf Community shelf -> GREAT IDEAS START HERE!! NEW PHYSICS CLUB DETAILS AND ADMISSION QUESTIONS: -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]
47 replies   
1) T
2) F
3) d
4) d
5) a/b
 
 
Go to:   

Top Offers for goIITians
Correspondence Courses
Brilliant Tutorials
Narayana Institute
Aakash Institute
Classroom/Crash Courses
Narayana - Kota , Delhi , Others
Brilliant Tutorials - Class , Crash
Aakash Institute - Medical , Engg
Online Test Series
Brilliant Tutorials
Narayana Institute
Aakash Institute
Mahesh Tutorials
AMITY      Sri Chaitanya