What is the basis of the Relativity Principle?
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Galileo's principle of relativity essentially states that, regardless of an observer's position or velocity in the universe, all physical laws will appear constant. From this principle, it follows that an observer cannot determine either his absolute velocity or direction of travel in space.\n\nhttp://farside.ph.utexas.edu/teaching/jk1/lectures/node7.html\n\nhttp://en.wikipedia.org/wiki/Principle_of_relativity
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Special relativity (SR) or the special theory of relativity is the physical theory published in 1905 by Albert Einstein in his article "On the Electrodynamics of Moving Bodies". It replaced Newtonian notions of space and time and incorporated electromagnetism as represented by Maxwell's equations. The theory is called "special" because it applies the principle of relativity only to the "restricted" or "special" case of inertial reference frames in flat spacetime, where the effects of gravity can be ignored.\n\nSpecial relativity inter-relates space and time in such a way that the speed of light is constant, and the theory leads to situations where two observers can disagree over time intervals and distances between events, but without ever disagreeing about what events actually happened. It shows that time can pass more slowly if an observer is moving, depending on their relative speed.\n\nThe theory also predicts the famous equation E=mc². Special relativity applied to objects travelling close to the speed of light as opposed to the lower speeds covered by Newtonian theory. It is now well established although Newton's methods are commonly used to cover slower objects.
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Interesting question.  I'll give a hand waving argument.  Assume the Theory of Relativity is true.  I'm not so sure I believe it, but assume it is true.\n\nYou start your trip with a certain amount of fuel, which you thought would be sufficient using the ordinary laws of classical physics. As you accelerate you have to use fuel.  To you there is no increase of mass, no increase in fuel.  You feel the acceleration, and that is all.  However, after awhile it seems that you are not gaining velocity relative to the "stationary" stars as you thought you should be.  You keep using up your fuel, of whatever type you brought with you, and you continue to feel the same force of acceleration that you did, but it seems to be having less and less effect in getting you up to the velocity you want.  Eventually you run out of fuel, at something less than the speed of light relative to the earth you left.  What went wrong?  It takes more and more energy to increase velocity with respect to the earth, because with respect to earth your mass has increased, though as far as you are concerned you cannot measure any increase in your mass.  It is just the fundamental paradox of the Theory of Relativity.
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this is where relativity comes into play. It depends from what viewpoint. speed is always relative to a "fixed" point (which might not be so "fixed" after all). get my drift?
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General relativity is the geometrical theory of gravitation published by Albert Einstein in 1915. It unifies special relativity and Isaac Newton's law of universal gravitation with the insight that gravitation is not viewed as being due to a force (in the traditional sense) but rather a manifestation of curved space and time, this curvature being produced by the mass-energy content of the spacetime.\n\nmore info for you :)
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Here are the postulates:\n\n(1) The laws of physics are the same as viewed from the perspective of any observer moving at a constant speed.\n(2) The value of the speed of light (denoted "c") is the same in every reference frame.\n\nThe first condition isn't very strange: You'd expect physics to be the same if you were on a very smoothly moving train as you would if you were standing on the Earth.\n\nThe second condition is very strange: Suppose you have two people moving with respect to each other.  One of them is moving at 1/2 the speed of light and the other is moving at 1/4th the speed of light.  Now, a beam of light is passing by them.  They'll both measure the speed of that beam RELATIVE TO THEIR VELOCITY to be c.  \n\nNote that this is a big contrast between what we'd normally expect.  Suppose you were moving at 7 miles per hour and I threw a ball past you at 10 miles per hour.  You'd see the ball moving away from you (another way of saying "moving relative to you" at 3 miles/hour because 10 mph - 7 mph = 3 mph).\n\nIn our light example we just saw that both observers measure the velocity of light relative to their own velocity to be the same.  It'd be like if your friend was moving at 5 miles per hour and you were moving at 3 miles per hour and you both claimed the ball was moving away from you at the same rate.\n\nAt any rate, what this is meaning is that neither time nor space is an absolute quantity.  If you were to observe a rocketship moving near the speed of light (as measured with respect to you), you would observe:\n\n(a) That the rocket appears to contract (shrink) in it's direction of motion, and\n(b) Events aboard the spaceship would appear to occur more slowly.\n\nHowever, they would measure the same things happening to you and the events along the spaceship to be proceeding normally.\n\nThat is only a very brief introduction.  If you'd like a better, but still accessable to a non-scientist, account of this I suggest you consider reading http://casa.colorado.edu/~ajsh/sr/sr.shtml .
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Well\nrelativity \n\nPhysical theory, introduced by Albert Einstein, that discards the concept of absolute motion and instead treats only relative motion between two systems or frames of reference. One consequence of the theory is that space and time are no longer viewed as separate, independent entities but rather are seen to form a four-dimensional continuum called space-time. Full comprehension of the mathematical formulation of the theory can be attained only through a study of certain branches of mathematics, e.g., tensor calculus. Both the special and general theories have been established and accepted into the structure of physics. Einstein also sought unsuccessfully for many years to incorporate the theory into a unified field theory valid also for subatomic and electromagnetic phenomena.\n\nEvolution from Classical Theory\n\nThe modern theory is an extension of the simpler Galilean or Newtonian concept of relativity, which holds that the laws of mechanics are the same in one system as in another system in uniform motion relative to it. Thus, it is impossible to detect the motion of a system by measurements made within the system, and such motion can be observed only in relation to other systems in uniform motion. The older concept of relativity assumes that space and time are correctly measured separately and regards them as absolute and independent realities. The system of relativity and mechanics of Galileo and Newton is perfectly self-consistent, but the addition of Maxwell's theory of electricity and magnetism to the system leads to fundamental theoretical difficulties related to the problem of absolute motion.
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That would be Einstein's Special Theory of Relativity.\n\nhttp://science.howstuffworks.com/relativity3.htm
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You can go to http://en.wikipedia.org/wiki/Main_Page to look up different scientific theories like theory of relativity http://en.wikipedia.org/wiki/Theory_of_relativity or Newton's Laws on Motion http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion\n\nGood Luck!!!
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http://en.wikipedia.org/wiki/Theory_of_relativity
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Relativity, as known to Galileo and Newton, refers to the idea that motion is relative to the observer.  Giving a simple example, on a calm day standing outside my house I think the air is not moving, while my friend riding in the back of a pickup truck feels the air blowing in his face.  However, both Newton and Galileo still believed there existed an "absolute" motion, as measured by the unchanging framework of the universe.\n\nWith the theory of Special Relativity in 1905, Einstein changed all that and revolutionized physics.  The main idea of special relativity is that the laws of physics should be the same for all observers moving at a constant speed. (Acceleration is not addressed in Special Relativity, but both acceleration and gravity are included in General Relativity, which Einstein formulated 10 years later.)  According to Special Relativity, there are no such things as absolute rest or absolute motion - speed and motion can only be measured against an arbitrary frame of reference, and one reference frame is as valid as any other.  Special Relativity also includes the concept that light travels at an absolute speed which is the same for all observers, regardless of the motion of the observer or the light source. Building on this concept, Special Relativity shows us that not only is motion relative, but so are many other familiar concepts like distance, time, and even energy.  In other words, different observers moving at different speeds will measure quantities such as length, time, and energy differently.  But each observer's measurement is equally valid.  It is the relativity of time that gives us the famous "twins paradox", where an astronaut travelling at very high speeds will age less rapidly than his twin back home on Earth.  Finally, Special Relativity gives us  the famous equation E=mc2, which establishes the equivalence of mass and energy.  All of these ideas were revolutionary and marked the end of Newtonian physics, which had reigned unchallenged for nearly 300 years.
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Rocket Principles\nA consquence of Newton's laws of motion is that for any object, or collection of objects, forces which only involve those objects and nothing else ("internal forces") cannot shift the center of gravity. For example, an astronaut floating in a space suit cannot shift his position without involving something else, e. g. pushing against his spacecraft. The center of gravity--or "center of mass"--is a fixed point, which cannot be moved without outside help (turning around it, however, is possible).\n\nBy throwing a heavy tool in one direction, the astronaut could get moving in the opposite direction, though the common center of gravity of the two would always stay the same. Given a bottle of compressed oxygen, the same result follows from squirting out a blast of gas (a scene that appeared in an early science fiction film). A rocket does much the same, except that the cold gas is replaced by the much faster jet of glowing gas produced by the burning of suitable fuel. At present, rockets are the only means capable of achieving the altitude and velocity necessary to put a payload into orbit.\n\nA rocket engine is a machine that develops thrust by the rapid expulsion of matter. Most rockets today operate with either solid or liquid propellants. The word propellant does not mean simply fuel, as you might think; it means both fuel and oxidizer. The fuel is the chemical rockets burn but, for burning to take place, an oxidizer (oxygen) must be present. Jet engines draw oxygen into their engines from the surrounding air. Rockets do not have the luxury that jet planes have; they must carry oxygen with them into space, where there is no air.\n\nThere are a number of terms used to describe the power generated by a rocket. \n\n\nThrust is the force generated, measured in pounds or kilograms. Thrust generated by the first stage must be greater than the weight of the complete launch vehicle while standing on the launch pad in order to get it moving. Once moving upward, thrust must continue to be generated to accelerate the launch vehicle against the force of the Earth's gravity. To place a satellite into orbit around the Earth, thrust must continue until the minimum altitude and orbital velocity have been attained or the launch vehicle will fall back to the Earth. Minimum altitude is rarely desirable, therefore thrust must continue to be generated to gain additional orbital altitude.\n\nThe impulse, sometimes called total impulse, is the product of thrust and the effective firing duration. A shoulder fired rocket has an average thrust of 600 lbs and a firing duration of 0.2 seconds for an impulse of 120 lb-sec. The Saturn V rocket, used during the Apollo program, not only generated much more thrust but also for a much longer time. It had an impulse of 1.15 billion lb-sec.\n\nThe efficiency of a rocket engine is measured by its specific impulse (Isp). Specific impulse is defined as the thrust divided by the mass of propellant consumed per second. The result is expressed in seconds. The specific impulse can be thought of as the number of seconds that one pound of propellant will produce one pound of thrust. If thrust is expressed in pounds, a specific impulse of 300 seconds is considered good. Higher values are better. A rocket's mass ratio is defined as the total mass at lift-off divided by the mass remaining after all the propellant has been consumed. A high mass ratio means that more propellant is pushing less launch vehicle and payload mass, resulting in higher velocity. A high mass ratio is necessary to achieve the high velocities needed to put a payload into orbit.\n\nThere are three categories of chemical propellants for rocket engines: liquid propellant, solid propellant, and hybrid propellant. The propellant for a chemical rocket engine usually consists of a fuel and an oxidizer. Sometimes a catalyst is added to enhance the chemical reaction between the fuel and the oxidizer. Each catego
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Theory of Relativity- Light is the one speed that does remain constant.
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Yes.  The laws of relativity have been shown to be true at various speeds.  At slow speeds the effect is very, very tiny, so it is very hard to measure, but every bit of evidence we have says that relativity is true for all speeds (and for being stationary, for that matter).\n\nWhy is it hard to measure?  Well, say you're in a small (2 meter) automobile going 100 km/hr.  The contraction due to relativistic effects would be about .2 micron, or 200 nanometers.  To see a contraction of just two cm - just under an inch - you would have to get the car up to 95 million miles an hour!  \n\nTime, momentum, mass, etc are likewise.  They are affected relativistically, but the effect is so very small that for all practical purposes it is zero.  \n\nBut maybe you have an impractical purpose??  :-)
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No.  The theory of relativity states that an object moving at a high enough velocity will appear to shrink along the direction of motion and increase mass from the point of view of a non moving observer, so much so that, if a physical object would be to travel at the speed of light, its dimension will be zero and its mass infinite.
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It's called relativity because it shows that time and space are relative to the observer, and can be perceived differently from other reference frames. \n\nWhat's this about collisions?
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try these links\nthts a really good question but its explainations is quite lengthy. so maybe if u go through all these links, u might get wat u really are looking for\n\nwww.muppetlabs.com/~breadbox/txt/al.html\n\nwww.bartleby.com/173/\n\nwww-groups.dcs.st-and.ac.uk/ ~history/HistTopics/General_relativity.html \n\nen.wikipedia.org/wiki/Theory_of_relativity\n\nwww2.ncsa.uiuc.edu/Cyberia/NumRel/GenRelativity.html\n\ngood luck and have fun!