If very heavy metal ruler was made to move at the speed of light would  force of gravity make it shink ?
352135
Nothing actually shrinks when you move. If you are moving with that object it will still have the same length as it did when you were not moving. Remember motion is relative to frames of reference and there is no prefered frame of reference.
1083768
Good question.  The reason is because gravity isn't actually pulling the light.\n\nGravity is much like a trampoline.  Imagine a bowling ball in the middle.  The ball creates an indention.  If you rolled a marble across the trampoline, and it traveled into that indention, it would curve around not because the bowling ball pulled it, but because it was following the contour of the trampoline.\n\nThis is how mass affects spacetime.  The sun or any mass for that matter creates an indention in spacetime.  The Earth is traveling in the Sun's spacetime indention, so it isn't the Sun pulling the Earth at all.\n\nWhen light enters the indented space, it follows the contour of the curved space, which is why it bends.
136380
This is actually a very deep and interesting question.\n\nIt is believed that gravity travels at the speed of light. So yes, gravity does have a speed. The postulated particles that might carry the gravitational force, gravitons, would travel at the speed of light. \n\nIf the earth were removed, the moon would not immediately fly off, because the curavature of space-time would take a finite time to get there. \n\nThis was recently measured and verified as Jupiter passed in front of a quasar, and the gravity of Jupiter bent the radio waves from the quasar. Using the equations of general relativity and the observations of this bending, it was verified that gravity does travel at roughtly the speed of light (see attached reference). \n\nHowever, there is some controversy concerning the validity of the measurement (see 2nd reference).\n\nIn Newtonian mechanics, gravity has to act instantaneously to conserve angular momentum. However in General Relativity, this extra angular momentum is carried away by gravitational radiation i.e., a gravity wave (see 3rd and 4th references)
148002
It's technically impossible for something with mass (like a spacecraft) to go the speed of light in our universe under the laws of physics.  As something approaches the speed of light, it gains mass.  In theory, if something were to actually go the speed of light, it would have infinite mass, which is impossible.  \n\nOf course, no one can say for sure.  Science fiction on television and in books have gotten around these rules by using wormholes, subspace, etc., none of which are known to actually exist.
428514
The speed of the graviton, the theoretical virtual particle which carries the gravitational force, is equal to the speed of light (the photon).  No effects (with the possible exception of quantum entanglement) can travel faster than the speed of light, and gravity is no exception.  In fact, if the sun were to disappear right now, our orbit would not be affected for nine minutes, the same time it would take for the light from the sun to cease.
630060
Speed of.. gravity? :S
649714
lots of gravity,  bends anything.
546164
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??  :-)
836797
If you are asking about anti-gravity cos you've seen an episode of star trek who's anti gravity engines run on anti matter then the answer is NO.\nI saw a program on the Sci-fi channel a few years back and an American guy had made a circular pad with about 1 metre radius which once turned on you could put any thing on it and it would just float in mid air, this guy just built it at his own leisure.\n\nThe question of moving at light speed is impossible for nearly anything except light, scientist now believe that it would be more feasible to bend space around an object so it would instantaneously leave one point in space and reappear in another
676832
YES\n===\nEverything is relative so in relation to some other object in space, yes it would be completely stopped as the train slowed down from the impact.\n\nNO\n==\nEverything in the universe is in constant motion.
416838
You may be confusing acceleration with velocity. An object in motion will remain in that motion unless a non-zero net force is applied to it. If you are in the void of space, and are traveling along at a particular velocity, you will remain at that velocity. On Earth, drag and other forms of friction will slow you down.\n\nAcceleration is different. For something to continue to accelerate, a constant non-zero net force must be applied to it.\n\nacceleration = force/mass so if I have a mass of 50kg and want to accelerate at 100m/s^2 (100 meters per second per second) then I need a constant force of 5000 newtons applied to me. Keep in mind that that is 5000 newtons relative to ME.\n\nNow, according to our current understanding of light, it would take an infinite amount of energy to reach speed of light because force = mass/acceleration and as you accelerate, your mass increases! Neither you nor I will notice this effect in our daily life but it becomes more noticable as you approach the speed of light. This does not create mass in the sense that new mass is appearing in the universe, it just adds more weight (no pun intended) to the mass that's already there. This is actully called the reletivistic mass. Your mass when you're at rest, is your rest mass.\n\nThough we won't be traveling close to the speed of light any time soon, there have been plans to get humans to high speeds without killing them. One such way is to accelerate in intervals. For example, you feel a strong force when taking off in an airplane but once the airplane reaches a few hundred miles per hour, and you've caught up, you can do it again.
371595
approx 19 miles/second.\n\nAny force from centripetal acceleration you might feel would be more than compensated by the gravitational attractions from the Sun and Earth themselves.\n\nIt might be a measureable amount, but just barely.
618210
Not due to gravitational pull?!
689820
Neither you, nor the train, could ever travel at the speed of light since both of you have some non-zero rest mass.\nIn order to accelerate something with a non-Zero rest mass, an infinite amount of energy would be required....and in the whole universe, there is not an infinite amount of energy.\n\nBut lets say you were traveling just under the speed of light...at 99.99999999999999% of c and you began to run toward the front of the train, \nyou would still NOT be traveling at or above the speed of light (as seen from an outside, "stationary" observer) since at relativistic speeds such as this, velocities do not add in the normal Galilean way, you would still be traveling slower than the speed of light.
500819
Your question is completely hypothetical. Light travels. Gravity does not. Interesting scenario, however. If such were to happen, I really don't know what the answer would be.
219491
Light definitely is bendable by gravitational field, but it is definitely not bendable by electromagnetic, simply because light itself is an electromagnetic wave. If light is bendable by other lights, then you should be able to meet two flashlight's light together and see that the lights bend, which is currently, I don't see
12398
The rotational energy you impart to the object when spinning overcomes the force of gravity that would topple a stationary object.  \n\nA total layman's explanation:\n\nA perfect stationary top perfectly balanced will not fall over.  In real life though,it's impossible to perfectly balance a top.  It's shape practically guarantees that its center of gravity will not be directly over the balance point for any practical length of time.  Imperfections in the material will cause a slightly uneven weight distribution, air currents will introduce a small force, and mechanical vibrations will be transmitted through the medium the top rests on.  The upshot of all this is that as soon as the center of mass is no longer over the resting point, gravity is going to pull the top over.  \n\nNow gravity has an acceleration of 32 feet per second squared (if I remember my ancient high school course correctly).  It can only topple the top at a specific speed.  If you spin the top fast enough, any side that gravity tries to "pull down" will translate around so quickly that it literally has no time to fall.  If you were standing on a planet with a much higher gravity, you'd have to spin the top far faster to achieve stability, and if you were on the moon, it would spin for a much longer time. Eventually, however, the top starts to slow and the tip will inscribe little circles.  That action is called "precession".  And of course, eventually the thing drops to the table and the game is all up once it slows enough.\n\nAgain, that's a layman's view of how it works.  Some college physics major is probably going to come in here and make my answer look really foolish.