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When we began to study electric forces we introduced the concept of the electric field, . In particular, we had the fundamental relation between the force on a charge q in an electric field: = q. We will introduce a magnetic field in a similar manner. Before doing this, however, we define what is known as the cross product x between two vectors and . Consider two such vectors in the plane of this page with an angle between them, as in Fig. 1.1. Figure 1.1: Two vectors x , which itself is a vector, is defined as follows: the magnitude of x is given by | x | = ||| sin V1V2sin , (1)
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submitted by Urva (187 m) on 14 May 2007 15:10:29 IST (0 comments 174 views)
Most people think that IIT JEE is very difficult examination. However, JEE is only a different examination.One thing certain is IIT JEE requires a very systematic preparation. Earlier you start preparing for it the better.JEE defers from conventional board exams in one major way. JEE tests your fundamentals of the subject and your ability to think logically and analytically.To begin with, you must arrange for professional guidance, if you do not have one available at home. Secondly, practice of solving JEE level problems being of paramount importance, you must have access to enough recommended books / notes.(1) You can get join postal / classroom coaching.(2) You ca
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submitted by sravan (183 m) on 14 May 2007 12:06:47 IST (0 comments 144 views)
Explain tliefollowilig 1. The radius of anion is greater than atom while that of cation is lesser than atom. 2.Half-filled and fully-filled orbitals are more stable. 3. The first ionization energy of carbon atom is greater than that of boron whereas the reverse is true for the second ionization energy. Explain. 4. The first ionization potential of N is maximum as compared to those of C and 0. 5. The ionic size of Cl- ions is greater than that of K+, though the two Ions are isoetectronic, Give reasons. 6. The electron affinity of chlorine is greater than that of F. 7. The electron affinity of sulphur is greater than that of oxygen. 8. The electron aff
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submitted by sravan (183 m) on 14 May 2007 10:15:48 IST (0 comments 71 views)
1. How many photons of light having a wavelength of 420 nm are necessary to produce 1.2J energy ? 2. Calculate wave number and frequency of radiations having wavelength 5800. 3. Calculate the energy in eV of (i) He+ and (ii) Be 3- in the first excited state. 4. Calculate ratio of de-Broglie wavelength of electron to proton moving with a velocity of 10^5 m/sec. 5. Find out the number of waves made by Bohr electron in one complete revolution in its third orbit. Also calculate the number of revolutions per second that this electron makes around the nucleus? 6. Calculate uncertainty in position of a particle when uncertainty in the momentum is (a) 1 x 10^-2, g
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submitted by sravan (183 m) on 14 May 2007 10:12:50 IST (0 comments 80 views)
1.Density of water at room temperature is Ig/ml. How many molecules are there in a drop of water, if its volume is about 0.05ml.? 2.How many molecules are present in 12L of liquid CC14? the density of the liquid is 1.59 g/cm^3 3.A solution contains 0. 18 g. per ml of a substance X, whose molecular weight is approximately 68,000. It is found that 0.27 ml. of oxygen at 760 mm. Hg. and 37C will combine with the amount of substance of X contained in one ml. of the solution. How many molecules of oxygen combine with one molecule of X? 4. 13.4 g of a sample of unstable hydrated salt: Na2SO4. xH20 was found to contain 6.3g of water. Determine the number of water of c
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submitted by sravan (183 m) on 14 May 2007 10:10:53 IST (0 comments 66 views)
Previous iit-jee mole concept questions Assignment Level-I 1) . a) Calculate the mass of 5 gram atoms of calcium. Atomic mass of alcium is 40. b) Calculate the mass of 1.5 gram molecules of water. 2) Calculate the number of gram atoms and gram molecules in 25.4 mg of iodine (12). Atomic mass of I = 127 amu. 3) How much sulphuric acid (H2SO4) can be obtained from 5 kg of pure sulphur (S8). 4) What is the molar volume of water at 273 K. Density of water = 1.00 gm/ cm^3. 5)
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submitted by sravan (183 m) on 14 May 2007 10:07:42 IST (0 comments 96 views)
What is the hottest place on Earth? Count one wrong if you guessed Death Valley in California. True enough on many days. But El Azizia in Libya recorded a temperature of 136 degrees Fahrenheit (57.8 Celsius) on Sept. 13, 1922 -- the hottest ever measured. In Death Valley, it got up to 134 Fahrenheit on July 10, 1913. What makes thunder? If you thought, "Lightning!" then hats off to you. But I had a more illuminating answer in mind. The air around a lightning bolt is superheated to about five times the temperature of the Sun. This sudden heating causes the air to expand faster than the speed o
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submitted by sravan (183 m) on 14 May 2007 09:30:34 IST (1 comments 65 views)
hey boyz n gals it is imp. topic in entrance exams so i want to throw light on this topic i hope it will benefit uRADICAL AXIS The radical axis of two circle axis is locus of point , which moves so that the lenghts of tangents drawn from it to the two circles r equal if S1 be equation of one cirle and S2 be equation of another circle than S1-S2=0is equation of common chord however same becomes equation of common tangent if circle touches each other RADICAL CENTRE let S1=0, S2=0 ,S3=0 be three circles then their radical axis taken in pairs r parallel or concurrent .if they r not parallel their points of concurrency is called radical centre of circles RADICAL CIRCLE l
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submitted by shubham.123 (307 m) on 13 May 2007 22:37:24 IST (2 comments 181 views)
Organic Chemistry is a challenging subject. It uses its own language and employs many very precise concepts yet without referring mathematical tools or aspects. Within first few hours of study you will be able to use the basic concepts to understand a lot about the molecular world around you. The first difficulty a student encounters is the amount of study material available about organic molecules and their reactions any standard text book is not less then 1400 pages long, a student cannot expect to learn all this material without investing a considerable time and effort in studying it and if he does so he disproportionates his time allocations with other subjec
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submitted by sauravagarwal (418 m) on 13 May 2007 14:52:16 IST (1 comments 171 views)
Indian Army To Get World's First Supersonic Cruise Missiles The BrahMos surface-to-surface missile. The Indian Army will become the first military force in the world to operate supersonic cruise missiles when it deploys the BrahMos surface-to-surface missile next year. The missile is expected to be deployed by September 2007. The joint Indo-Russian BrahMos has a 180-mile range. The India Daily reported on July 24 that analysts believe that deploying the BrahMos in large numbers could give India an assist in its arms balance with Pakistan. Indian artillery officers estimate that around 90 mobile launch
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submitted by INDIAN_ARMY19890 (1265 m) on 25 Apr 2007 19:35:04 IST (3 comments 261 views)
In order to have a clear picture of where you are charting in your career and what you would like to accomplish from your career, you must have a clear set of career goals. It may be a good idea to write down exactly what you would like to achieve, how much money you would like to make, and what type of tasks you would like to do. In order to achieve career goals, follow the following steps. It is not likely to be possible to achieve the ultimate career goal in one step. Take it step-by-step and be patient. Be creative to think about different ways by which you can accomplish your goal. Do not be afraid to reach a little higher than what you think you might achie
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submitted by sauravagarwal (418 m) on 13 May 2007 14:49:13 IST (0 comments 86 views)
Person should not be too honest. Straight trees are cut first and honest people are screwed first." Even if a snake is not poisonous, it should pretend to be venomous The biggest guru-mantra is: Never share your secrets with anybody. ! It will destroy you There is some self-interest behind every friendship. There is no friendship without self-interests. This is a bitter truth Before you start some work, always ask yourself three questions - Why am I doing it, What the results might be and Will I be successful. Only when you think deeply and find satisfactory answers to these questions, go ahead As soon as the fear approaches near, attack and destroy it. The
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submitted by Harshad (0 m) on 13 May 2007 13:31:02 IST (1 comments 167 views)
Finger Math: 9X Rule To multiply by 9,try this:(1) Spread your two hands out and place them on a desk or table in front of you.(2) To multiply by 3, fold down the 3rd finger from the left. To multiply by 4, it would be the 4th finger and so on.(3) the answer is 27 ... READ it from the two fingers on the left of the folded down finger and the 7 fingers on the right of it.This works for anything up to 9x10! Square a 2 Digit Number Ending in 5 For this example we will use 25 Take the "tens" part of the number (the 2 and add 1)=3 Multiply the original "tens" part of the number by the new number (2x3) Take the result (2x3=6) and put 25 behind it. Resul
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submitted by akshaybansal (312 m) on 11 May 2007 23:47:04 IST (7 comments 255 views)
In physics, a laser is a device that emits light through a specific mechanism for which the term laser is an acronym: light amplification by stimulated emission of radiation. This is a combined quantum-mechanical and thermodynamical process discussed in more detail below. As a light source, a laser can have various properties, depending on the purpose for which it is designed. A typical laser emits light in a narrow and well-defined beam and with a well-defined wavelength (or color). This is in contrast to a light source such as the incandescent light bulb, which emits in almost all directions and over a wide spectrum of wavelength. These properties can be summarize
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submitted by akshaybansal (312 m) on 13 May 2007 01:11:15 IST (0 comments 91 views)
Here i would like to give some brief theorms of circle, Properties of a Circle Circle Theorems: Angles and chords Angles Chords Tangents Cyclic Quadrilaterals setImgWidth(); setImgWidth(); setImgWidth(); setImgWidth(); setImgWidth(); setImgWidth(); setImgWidth(); setImgWidth(); This thread is continued...here, http://www.goiit.com/posts/list/0/community-shelf-circle-geometry-properties-of-a-circle-with-12464.htm#70333 P.S :- This is not a google search, copy and paste art
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submitted by vinod (1433 m) on 11 May 2007 21:58:40 IST (6 comments 359 views)
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