According to einstein, the gravity as we have learned in the 11th and 12th is a wrong concept. The newtons simple law that says that two particles attract with forces that is equal to GMm/r² is only true in the calculation point of view. But in relativistic cases, things act a lot differently, and the newtons gravitational equation never holds. Actually newtons equation is only applicable for big objects going at a speed very lower than the speed of light.

According to einsteins space curvature concept, gravity never pulls. The gravitational force of a massive body will only bend the space, into which a a body can fall. And the way it falls is in a spiral and is shown in many famous museums in bangalore etc. That is how the planets revolves around the sun. And when the space curvature gets more deep, the body falls faster,  which is equivalent to a higher value of g in newtonian concept. And in the most extreme case, the space curvature almost becomes rectiliniar and that is when even light cant escape, and it becomes a black hole. A spiral black hole that satisfies certain condition is a worm hole where you can travel in time. The critirea for time travel is a very high speed, faster than the speed of light (Although according to einstein it is not even possible as high velocity means high mass (by relativity equations) which will need infinite fuel to travel. But controversely, its said to be practical in a worm hole which can connect two different places like galaxies or maybe even another universe.)

The things i explained are very low in detail as i can go on for ever. The newtonian concept called classical physics can only be used in normal cases but not in relativistic cases. Check out books of stephen hawkins, a universe in a nutshell and brief history of time are easy to understand. In all those books its explaines well that the gravity as we are learning for years for IIT-JEE is purely fictional in the current world. Although it gives a very nearly correct answer in the normal cases, the thing called gravitational pull among two bodies doesnt even exist. Its all about space curvature. Why are we learning wrong concepts?

PS: Einstein is cool.

Simply becoz IITs dont want rocket scientists for their UG programmes.

U R taught ONLY basics for IITJEE. All these higher concepts are taught in higher studies.

First of all, classical mechanics is not only Newtonian mechanics. Rather, all physics done before 1900 is referred to as classical.

Secondly, as for "why are we learning wrong concepts?", I shall quote Richard Feynman:

"You might ask why we cannot teach physics by just giving the basic laws on

page one and then showing how they work in all possible circumstances, as we do

in Euclidean geometry, where we state the axioms and then make all sorts of deductions.

(So, not satisfied to learn physics in four years, you want to learn it in

four minutes?) We cannot do it in this way for two reasons. First, we do not yet

know all the basic laws: there is an expanding frontier of ignorance. Second, the

correct statement of the laws of physics involves some very unfamiliar ideas

which require advanced mathematics for their description. Therefore, one needs

a considerable amount of preparatory training even to learn what the words

mean. No, it is not possible to do it that way. We can only do it piece by piece.

Each piece, or part, of the whole of nature is always merely an approximation

to the complete truth, or the complete truth so far as we know it. In fact, everything

we know is only some kind of approximation, because we know that we do

not know all the laws as yet. Therefore, things must be learned only to be unlearned

again or, more likely, to be corrected.

The principle of science, the definition, almost, is the following: The test of

all knowledge is experiment. Experiment is the sole judge of scientific "truth."

But what is the source of knowledge? Where do the laws that are to be tested

come from? Experiment, itself, helps to produce these laws, in the sense that it

gives us hints. But also needed is imagination to create from these hints the great

generalizations—to guess at the wonderful, simple, but very strange patterns beneath

them all, and then to experiment to check again whether we have made the

right guess. This imagining process is so difficult that there is a division of labor

in physics: there are theoretical physicists who imagine, deduce, and guess at new

laws, but do not experiment; and then there are experimental physicists who experiment,

imagine, deduce, and guess.

We said that the laws of nature are approximate: that we first find the "wrong"

ones, and then we find the "right" ones. Now, how can an experiment be "wrong" ?

First, in a trivial way: if something is wrong with the apparatus that you did not

notice. But these things are easily fixed, and checked back and forth. So without

snatching at such minor things, how can the results of an experiment be wrong?

Only by being inaccurate. For example, the mass of an object never seems to change;

a spinning top has the same weight as a still one. So a "law" was invented:

mass is constant, independent of speed. That "law" is now found to be

incorrect. Mass is found to increase with velocity, but appreciable increases require

velocities near that of light. A true law is: if an object moves with a speed of

less than one hundred miles a second the mass is constant to within one part in

a million. In some such approximate form this is a correct law. So in practice

one might think that the new law makes no significant difference. Well, yes and

no. For ordinary speeds we can certainly forget it and use the simple constantmass

law as a good approximation. But for high speeds we are wrong, and the

higher the speed, the more wrong we are.

Finally, and most interesting, philosophically we are completely wrong with

the approximate law. Our entire picture of the world has to be altered even though

the mass changes only by a little bit. This is a very peculiar thing about the

philosophy, or the ideas, behind the laws. Even a very small effect sometimes

requires profound changes in our ideas.

Now, what should we teach first? Should we teach the correct but unfamiliar

law with its strange and difficult conceptual ideas, for example the theory of

relativity, four-dimensional space-time, and so on? Or should we first teach the

simple "constant-mass" law, which is only approximate, but does not involve such

difficult ideas? The first is more exciting, more wonderful, and more fun, but the

second is easier to get at first, and is a first step to a real understanding of the

second idea. This point arises again and again in teaching physics. At different

times we shall have to resolve it in different ways, but at each stage it is worth

learning what is now known, how accurate it is, how it fits into everything else,

and how it may be changed when we learn more."

And finally to quote Einstein, " As the circle of light grows, so does the circumference of darkness around it."