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2007-03-05 18:28:49 · 8 answers · asked by Parth M 1 in Science & Mathematics Physics

8 answers

Oddly enough, light travels more quickly through a vacuum than it does through Earth's atmosphere. It's not really due to 'air resistance,' but unless you want to go into and beyond the quantum mechanics of it all, let's just say that, yes, it does effect the speed of light. You get the same effect with glass and water - refractions are due to light changing speed as it enters a new substance in which it travels either more quickly or slowly than the medium it just left.
Gravity, well, that goes without saying. Just look at a black hole - the gravity of such features can be so great as to not only change the velocity of light, but alter its path to such a degree that it gets sucked in. A change in direction can also be seen as an acceleration in a direction other than the initial - in other words, the light is accelerated towards the black hole. This is how we can detect black holes - light from stars directly behind them is sucked in, but light that would have passed close enough to the gravitational well of the hole without actually getting sucked in continues in a path bent by the well. This allows us t osee stars that are directly behind black holes, with some distortion. I'm not sure exactly how scientists tell the difference, but somehow the ycan tell from these distortions where black holes are.

2007-03-05 18:44:10 · answer #1 · answered by cameteoritefinder 2 · 2 1

Who were the first to calculate the velocity of light?

Rig Veda Bhashyam by Sayana Madhava gives the following
Sloka praising the Sun:

Yojanam sahasre dve, satadve, dvecha yojane
Ekena nimeshardhena kramamaana namosthuthe

One Yojana equals 15788.8 meters, and half of Nimesha
equals 8/75 fraction of a second. This gives the velocity
of light as 325940 km/s. We have to remember here that the
above value is an approximate one intended for easy
remembrance, like remembering the value of pi as 22/7. It
is better than the value 215000 km/s given by Danish
astronomer Ole Roemer in 1676. Having discovered so many
things, it is only logical to expect that our ancestors
must have used light as the standard for length
measurements; after all, modern science considers velocity
of light to be a Universal Constant! The word "kramamaana"
of the above Sloka has the hidden meaning of gradual
minute change which occurs over thousands of years.

Our ancient seers did not use light as a standard for
length measurement. How can that "which bends" be
called unchangeable? Every created thing is subject to
change by time; there is nothing like an universal
constant. And the velocity of light is no exception to
this law. The velocity of light of our Sun was greater
in Krita Yuga than what it is now, even if it is by a
small fraction. The velocity of light is proportional
to the stored energy in the Sun or any other star.
Modern science also accepts that the Sun has lost a lot
of energy over billions of years. Then, there must be
some other stars in the universe which have greater
stored energies than the Sun, and are emitting light
which is faster than that of the Sun? Yes. Modern
science will confirm this after it develops more
sophisticated equipment than what they have at present.

2007-03-07 15:17:41 · answer #2 · answered by Anonymous · 0 0

GRAVITY - No
AIR RESISTANCE - Yes. The speed of light (..300-million meters per second..) is only true for light moving in a complete and absolute vacuum. Light's movement through any medium, like air, water, glass, etc., is slowed slightly.

2007-03-05 19:20:24 · answer #3 · answered by Chug-a-Lug 7 · 1 0

gravity does not affect speed of light. it is for certain. it is because for gravity to have any effect light should be made of matter. light is only a form of energy and made of photons which cannot be affected by gravity. for air, air does can affect the speed of light. but usually since they have low density there is no slowing down of speed. density of air matters because as density increases speed of wave passing through it decreases. this in turn is due to decrease in free space between the molecules.

2007-03-05 21:04:45 · answer #4 · answered by Saagar M 1 · 0 0

It does!

The gravity is a force like all others, and cause light has a rest mass, its affected by forces. A light beam can be bend by gravity, like in astronomy, where the light is bend by the gravity of a star. Light can also be slown down by forces, like it is done by a black hole. The gravity force of a black hole is so strong, that the speed of light which whould be emitted from the surface of a black hole would reduce to zero. Thats why black holes emmit no light, thats why they are called black holes.

Air decreases the speed of light too, like any material, but not out of the normal air resistance u would imagine. The speed of light in a material is defined by the reflection index (c`=c/n). The reflection index of vacuum is 1. Giving light the maximum speed in vacuum, every other material has a value greater than 1, which slows speed down.

2007-03-05 18:46:21 · answer #5 · answered by Anonymous · 1 2

Air resistance doesn't. I believe Einstein postulated that a beam of light could be bent by gravity. This doesn't affect the SPEED of light, speed being a scalar quanity, but it would affect the VELOCITY of light in the initial direction.

2007-03-05 18:34:22 · answer #6 · answered by cattbarf 7 · 1 2

yes , gravity & air resistance affect speed of light

2007-03-05 18:52:46 · answer #7 · answered by peterparkerthomascharli 1 · 1 2

no

2007-03-05 18:31:09 · answer #8 · answered by Anonymous · 0 1

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