if two lights are emitted one after other?

Question

what will be the relative velocity of the first one with respect to the other light.

Answer 1

Zero

Answer 2

The relative velocity is exactly the velocity of light. According to the special theory of relativity, the velocity of light (c) is invariant in all inertial frames of reference. Simply put, whatever your velocity might be, you'll always see light moving at 'c'. The only conditon is that you must be moving at uniform speed in a straight line.

This means that whether you are gently jogging along or streaking through at 80% the speed of light, you'll always see light moving at the same old speed 'c'. Indeed, even if you were moving at the speed of light yourself, a ray of light, whether ahead of you, behind you or by your side, will appear to be moving at 'c' !

This seems impossible and ridiculous, but that's Einstein's relativity for you. The everyday rules of addition of velocities simply don't work as you get closer to the speed of light.

So while you can very accurately say that the velocity of a train moving at 95 kmph is 5 kmph relative to another moving at 90 kmph, you will be way out if try to use the same formula for two spaceships moving at 90% and 80% the speed of light.

In case you are interested, for calculating the velocity v' of a body moving at velocity u relative to another moving at velocity v is rather funny-looking :
v' = (u - v) / (1 - uv / c^2)
Note that when u & v are very small (as most of our everyday velocities are), the term uv/c^2 is vanishingly small and we get back our traditional formula v' = u - v. But if u = 0.9c and v = 0.8c, as in our above example, v' = 0.1c / (1 - 0.72) = 0.357c, whereas the everyday formula v' = u - v would give us 0.1c, which would be way, way wrong.

Now watch ! Suppose you are on a spaceship moving at v watching light moving at c. Plugging u = c in the funny formula, we get
v' = (c - v) / (1 - cv/c^2) = (c - v) / (1 - v/c) = c (surprise !),
which is what I said in my first paragraph up there : light always moves at 'c' relative to you, whatever your speed v might be.

By the way, won't you will be delighted to know that, when he was a small child, Einstein was asking himself the same question you're asking us now !

Answer 3

Since the speed of light is constant to any observer, any observer will see both beams of light travel at the same speed. Therefore, they would have 0 relative velocity. I'm assuming here that you meant the lights were sent in the exact same direction.

Answer 4

Since both are travelling at the speed of light, the relative velocity is zero

Answer 5

They have the same velocity......light velocity ......Einstein
Rel = 0

But I think You mean the time from seeing the click on of the first till You see the click on of the second light!

And then You see the second click on a little later !

So They have a relative Click-On time not = 0!

Einstein is easy! only think slow like a saurus and exact like an eagle!

Answer 6

I do not think this is a good question because the speed of light is not a strictly valid frame of reference.

Answer 7

Speed of light is too complicated to imagine and whatever answer we give may not be correct. We are living and thinking in terms of relationship. We can never conceive anything in absolute terms.

Without comparison or relationship we can not classify anything. This is like a blind man trying to imagine different things. I am sorry to give comparison of a blind person.

Answer 8

problem child has said it all!!!!!
ya speed of light!

Answer 9

If you mean two separate light sources then I believe zero velocity is the correct answer

If you mean two separate light quanta particles from a singular source then the answer would be dependent upon multiple factors which must exist with in particle streaming.

Also to the question which you posed regarding Galaxy's traveling faster than the speed of light I attempted to edit it and give you added details but there was an error in submission and this was my response.

asked by arunjp1989

how can one say that galaxies travell at the speed of light?
at what ever velocity a galaxy travells light will travell 3*10^8 m/s more than the the velocity of galaxy.then how can galaxy travell at the velocity of light

Your Answer

Irregardless of whom sad it, the fact is that the possibility's must be examined as with respect to all galaxies linear direction, combined with angular momentum of galactic spin with respect given to quantum gravity of the quantum singularity which exists at galactic center of the Galaxy's, then with direct correlation to the space time curvature you could think of light then which leaves the stars with in galaxy star formations as expanding at, or with in, a variable rate of the expansion of our universe which is at, or near equal in all directions.

Also please consider that although Mr. Einstein believed that light quanta is invariant, that he may possibly have been incorrect, and the relative speed at which we are currently capable of measuring light quanta is only with direct relationship to our position with in a singular solar system in a singular galaxy which resides with in a entire Universe which by our accounts is in-measurable.

Therefore 3*10^8 becomes irrelevant, as that is merrily the speed at which we are capable of observing the phenomena from with in our point value reference state.

To sum it all up, we could easily compare, and imagine that light quanta represents a common insect the fly which travels under its own power with consideration given to the insects design from the back seat of an automobile to the front seat with all of the automobile windows in the up position. the fly will always traverse the distance in any, and, or all directions with the greatest of ease irrespective of the linear speed and direction of the automobile which in this instance represents itself to us as our galaxy.

Therefore I am suggesting that given so many unknowns in which the most basic is the functional mysteries of energy itself, and the manners in which energy expresses itself to us by design through invisible forces of gravity, magnetism, light, we must maintain an open mind and stop looking upon Mr. Einstein as an infallible God. which he was not, and we must continue to examine all of the wondrous possibility's with an open mind, as those whom have a closed mind will remain in the dark ages.

What I am suggesting, is that our limited understanding of the function of light quanta, has been calculated based upon our limited perceptions of how light quanta behaves with in our solar systems Oort cloud, and also in which even our own man maid satellite's have not reached the Oort clouds outer boundaries, and if we treat our limited perceptions as though they are an absolute fact for all functional behaviors of light, then we are only doing our selves a great disservice as the real truth will not be achieved until our limited perceptions have been adjusted.

The possibility must remain that we may not be correct, and also that even our understanding of math as we have designed it, and know it is inherently flawed.

We must remain open minded to, and continue to explore all alternative possibility's or our scientific greatness will stagnate just as it did in the Dark Ages, when it was widely taught that our planet was flat, and we could sail a ship over the end of it.

The only place where flat exists is with in the mind of mankind and in there limited perceptions of there truth as they are capable on understanding it.

I will pose you this question What if Light Quanta function was time independent between Oort Clouds and traverses vast distances between solor systems at a speed far greater then our current understanding.

The current truth and fact remains that we have never measured light speed outside of our Oort cloud, but have only been capable of measuring Light Quanta from with in it, therefore our current measurements of galaxy's in light speed may be inherently flawed.

Also the possibility must remain that blue shifting, and red shifting of light is only a reactionary affect of light quanta energy resonance shifting of an unbalance of motion from with in the design of the light quanta while passing through our Oort cloud particle energy field, just as we observe light which is divided by a prism and also refracted at oblique angles.

It is my wish that we all broaden our horizons by remaining open minded to all possible alternatives. I hope you receive this and it helps you.

Answer 10

O