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if you put your hands on a hot oven tray it can seem to last for hours. if you put them on a hot woman it only seems to last a few seconds

2006-10-24 11:39:57 · answer #1 · answered by Shnaricles the mythical panda 4 · 0 0

Take your spaceship with the powerful engine. It absolutely does NOT "gain mass" as it accelerates; that is a fiction promulgated by shitty high school text books. You and the other passengers feel exactly the same amount of acceleration for as long as that engine is running; you can accelerate like that for a day, a year, a century, forever, for as long as you have fuel. And indeed, the more you accelerate, the less time it will take to reach distant destinations. The more you accelerate, the greater your rapidity and celerity, and the quicker you will get to where you are going. What you CANNOT do is travel faster than c relative to any other body. The reason is simple, and it has nothing to do with mass or forces. It has to do with the way that spacetime is structured. In particular, the speed of every light ray is c, as measured by any one. So no matter how long you accelerate, a light beam always passes your ship at c. You can never catch up to that light ray, because no matter how fast you go relative to Earth, that light ray still passes you at c. Since you can never catch up to that light ray, no one can see you catch up to it, and so everyone will always agree that your speed is less than its.

2016-03-28 05:59:06 · answer #2 · answered by Anonymous · 0 0

Einstein himself made a pretty good job of the explanation in his book: 'Relativity - the Special and the General Theory'. The ISBN number is 0 416 67600 6.

If you are looking for a shortcut to the understanding of relativity then you will be faced with a variety of doubtful 'explanations'. I suggest that you refer to the work of the man himself - he makes it as easy to follow as it possibly can be.

2006-10-24 02:10:27 · answer #3 · answered by clausiusminkowski 3 · 0 0

Special Relativity:

In 1905 Einstein first published his Special Theory of Relativity. In this, he not only fixed a glitch in the physics world view, but he completely transformed our view of the universe in a way not properly appreciated, not even by physicists themselves.

The Special Theory of Relativity was a modification of Newton's laws, laws which had stood for three hundred years. By starting with two simple principles, one of which is very simple and one of which is utterly alien, he created a shocking system. He also reconciled the two warring fields of electromagnetism and traditional mechanics, and postulated the equivalence of matter.

There are two principles which Einstein proposed and which provided the basis for his entire theory. These two principles have been named the principle of relativity and the principle of the constancy of the speed of light. The first one should be familiar - it states that the laws of physics remain the same in every inertial reference frame, where that complicated phrase simply means the point of view of someone who is moving with a constant velocity. This is Newton's principle, mentioned earlier, re-iterated for extra emphasis. The second principle, the one which ensures the first one and which leads to very strange results, states that the speed of light remains the same for every observer. We explain this further in the next section.

By using these two principles, Einstein produced a number of remarkable facts: every observer will see a different universe, mass and energy are essentially the same thing, there is no such thing as an absolute velocity. A simple example - when you drive past a traffic light, it is equally valid to say that the whole world is moving backwards while you stand still as it is to say that you are moving forwards. These are the consequences of living in this strange, relative world.

General Relativity:

The General theory of relativity was developed by Einstein in 1915. In it he dealt with acceleration and gravity. Special Relativity could not handle gravity and acceleration so this can be thought of as an extension of Special Relativity to include gravity and acceleration.

Newton's law for gravity explains what happens. Objects attract other objects with a force inversely proportional to the square of the distance between them and those objects respond with accelerations proportional to the forces. This is very simple to understand. Objects attract each other and the further apart the objects are, the weaker the force of attraction. This explains why an apple falls down and not up.

Einstein saw the universe in a different way. He said that the universe is curved around heavy masses and objects always try to move in straight lines. Objects move the way they do near heavy masses because they are trying to move in straight lines in this curved space. This is a complicated explanation for apples falling down and not up.

Einstein based this theory on his Principle of Equivalence which, simply put, states that acceleration and gravity are equivalent in every way so that it is theoretically impossible to tell the difference between forces due to acceleration and forces due to gravity.

The General Theory of Relativity reinforced Einstein's reputation as the greatest thinker of his time. It gave birth to a whole new branch of physics, namely relativistic physics.

2006-10-24 01:25:46 · answer #4 · answered by djessellis 4 · 0 0

Galilean relativity is basically the following statement:

Any two observers moving at constant speed and direction with respect to one another will obtain the same results for all mechanical experiments.

Imagine you are in a plane without windows, and that it is travelling at constant speed (i.e. it is not accelerating). Galilean relativity means that you will be unable to tell at what speed you are travelling - you could be stationary (constant speed is zero), moving at 100mph or any other speed, there is no way to know.

Special relativity largely stems from the following fact:

The speed of light in a vacuum is a universal constant (c) which is independent of the motion of the light source.

This gives rise to a host of counter-intuitive effects such as time-dilation (whereby time can appear to run at different speeds to different observers), length contraction (whereby objects are contracted along their axis of movement), inertial effects (whereby moving objects gain mass, making them harder to accelerate) and the fact that two events occuring at the same time to one observer could be perceived by another observer as occuring at different times.

General relativity is EXTREMELY complex (and I don't profess to have a great understanding of it). It proposes that space and time are not separate but part of a single entity - space-time. The prescence of matter and energy curves space-time. This curvature of space-time results in what we know as gravity.

Hope this helps, but if you are really interested, try Wikipedia.

2006-10-24 03:10:37 · answer #5 · answered by msm1089 2 · 0 0

Tempus Fugit.

‘Time, it is relevant’, or so Einstein said,
It came from a notion, somewhere in his head,
But Pad won’t believe it; maybe he’s wise,
He said ‘Tempus Fugit’, or to you,‘ Time flies’.

Poor Einstein - his theory of relativity,
Was a sign, old Pad said, of naivety,
That theory is one thing that’s not in God’s plan
He’s said to have said, ‘Time waits for no man’.

If Einstein were right, what would a man do?
But fly back a few years, then forwards a few,
His antics they would be just like a woman,
‘Till no one knew if, he was goin’ or comin’.

‘You would be able to see, if Einstein were right,
Next week’s news headlines, sometime tonight,
And last years potatoes, the ones that you ate,
Would not yet be planted, or gathered as yet’.

‘You could meet your own son when he’s ninety-one,
Then see your own father, when his life begun,
Then kiss your own mother when she was a girl,
Life, if he’s right, would be all in a whirl’.

‘So take my advice’, Old Pad, thinks he’s right,
‘That Einstein was clever, and yes, very bright’,
‘His theories’ says he, ‘they surely won’t last’,
‘What’s done, it is done, and what’s gone, is the past’.


------------------------

2006-10-24 01:32:59 · answer #6 · answered by thomasrobinsonantonio 7 · 0 0

time slows down when you travel fast.

if you were flying fast enough to notice like in a spaceship, you may be gone for what you percieved to be one year but come back to earth to find that a year and a half has gone by.

if it was possible to see the people on earth whilst you were in flight, they would appear to you to be in fast forward, similarly they would see you in slow motion.

2006-10-24 16:34:23 · answer #7 · answered by davidtrueofvoice 2 · 1 0

Which one there are several.

There is Galilean relativity, General relativity and special relativity!

Let me know which one and I'll do my best...

2006-10-24 01:26:08 · answer #8 · answered by Mark G 7 · 0 0

we must determine mass, length, time when we are at rest. we reach certain amount but when we move with the velocity of V theb obtained answers is not perior answer . at velosity V we have mass= m0/1-c2/v2 m0 is mass at rest . similar formula holds true about length and time.

2006-10-24 01:45:56 · answer #9 · answered by eshaghi_2006 3 · 0 0

ok it basically describes the motion of particles moving at close to the speed of light.

ok i give up dw i dont get it either :P

2006-10-24 01:28:29 · answer #10 · answered by nikki 2 · 0 0

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