Speed of Light

It is known as a light year.

To turn off the speed warning light on a 2005 VW Jetta, you will need to access the vehicle's settings or instrument cluster menu. From there, you can adjust or disable the speed warning feature. Refer to the owner's manual for specific instructions on how to navigate the settings menu.

That is called "refraction", and it is related to the fact that light travels slower in some materials than in others.

The speed of air at 20 degrees Celsius is 343 meters per second. The speed of light is 299 792 458 meters per second.

The equation for velocity approaching the speed of light is given by the relativistic velocity addition formula: v = (u + v') / (1 + u*v'/c^2), where v is the relative velocity between two objects, u is the velocity of the first object, v' is the velocity of the second object, and c is the speed of light in a vacuum.

-- First of all, since the electron has rest mass, it can never move at the speed
of light.

-- Following DeBroglie, the electron's wavelength is such that an integral number
of them fit around the length of the electron's orbit when it's bound to an atom.

To accelerate an object with mass to the speed of light, you would need an infinite amount of force, as the closer an object gets to the speed of light, the more energy it would need to accelerate further due to the laws of relativity. Additionally, as of our current understanding of physics, it is impossible for an object with mass to reach the speed of light.

When you rigorously apply Maxwell's Equations to an accelerating charge, you find that an EM wave moves away from this charge. The E-field changes, resulting in a B-field; the B-field changes, resulting in an E-field. This process can be infinitely repeated with no loss of energy, as long as the EM wave travels through a vacuum. Thus, no loss in energy.

You also find if you do the above that this wave ALWAYS propagates at the speed of light when in a vacuum -- no exceptions. That's just the way our Universe operates.

The EM wave is NOT like a balling rolling on a floor. There is no frictional force on this wave that would cause a loss of energy or a slowing down.

Radio waves move faster in air.

Radio waves are an example of electromagnetic radiation, just as light is.

Just as materials have an index of refraction for light, they also have an index of refraction for radio waves.

All electromagnetic waves have the same speed in vacuum whether they are radio, light or gamma rays.

The speed of electromagnetic waves in a material is equal to the speed of light in a vacuum divided by the index of refraction for that type of wave. The index of refraction of glass for radio waves depends on the glass but is well above 1 whereas for air, it is more like 1.0001. A similar comparison can be made for visible light.

The index of refraction can, of course, be measured, but for air and glass one expects them to be quite different because there is a huge difference in the densities of the two materials. Air mostly empty space between molecules and so one expects electromagnetic waves to propagate at a speed very close to the speed in empty space.

As a very crude rule, one expects the long wavelength index of refraction for transparent materials to increase when the number of electrons in the medium increases.

Caveat: Statements made here would have to be modified if the energy of the electromagnetic wave were near an energy where it was absorbed by the medium.

The simplest answer is that light consists of particles with wave properties. Elementary particles also have wave properties. This is how light travels.

The speed of light, or c, is a constant. The speed of light is exactly 299,792,458 meters per second IN A VACUUM. That's 670,616,629.2 miles per hour or 983,571,056 feet per second.

Sure. But the magnifying glass can't squeeze any more heat out of your light source
than what the source has without the magnifying glass.

The only thing the magnifying glass does is take all of the light ... and maybe heat ? ...
that hits the magnifying glass and focus it down to a very small area. It has no more
heat or light to work with than what enters the glass.

The most efficient way to heat water with a light bulb is to shine the bulb straight up
and hang the pot over it.

No. It is proven that masses cause slight deviation in the path of light. The larger the mass, the more obvious the deviation.

Because it is. There's no fundamental reason that we're aware of why it should happen to have the precise value it does ... it just does.

One of the things physicists (especially cosmologists) have been interested in is figuring out if there's some underlying reason that certain physical constants have the values they do, or if they're more or less "random".

It turns out there IS a "reason" why some values are what they are, and that reason is "if they were very different, we wouldn't be here to ask the question." For example, if the color force were slightly stronger than it is, all the hydrogen in the early universe would have converted to helium ... and the universe would be full of helium and nothing else, making it impossible for us to exist.

This is called the "Strong Anthropic Principle", and it sounds a bit arrogant, but it's true: the universe is the way it is because it makes us possible. (The reason it's not really "arrogant" is that we're not necessarily saying that the universe had us in particular in mind when it was "deciding" what its physical constants should be ... just that the fact that we DO exist puts constraints on what the values could have been. Some cosmologists suggest that our universe is only one of many, and nearly all the others are dead, lifeless, boring places, because their physical constants are such that they preclude the development of life.)

Beyond the strong anthropic principle, there may well be fundamental reasons why the, say, fine structure constant is what it is (almost exactly, but not quite, 1/137). But we don't know what they are. Yet.

The speed of light is one of the factors in the fine structure constant, which is why it's particularly germane to your question. If the fine structure constant were different from what it is by more than about 3%, then stellar fusion could not produce carbon, and ... you guessed it ... we wouldn't be here to ask the question.

The shadow will fall on the opposite side that the light hit the object. Assuming that the object is a solid object that you cannot see through, there would be no light on the other side, hence causing the shadow.

There is no such concept as "eyesight speed"

162000 NM

speed of light in kilometers per hour is 299 000 kilometers per second X 60 gives you kilometers per minute X 60 gives you kilometers per hour.

Running speed is about 3 m/s

Light speed is about 300000000 m/s

That's 10^8 times faster

-- A car accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the car.

-- A stone accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the stone.

-- A Frisbee accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the Frisbee.

-- A baseball accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the baseball.

-- A dog accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the dog.

-- A book accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the book.

-- A canoe accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the canoe.

-- An airplane accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the airplane.

-- A planet accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the planet.

-- A cow accelerates in the direction of the net force on it, at a rate equal to the

magnitude of the net force divided by the mass of the cow.

You can't .

v2 = u2 + 2as = 1502 + 2*200*100 = 62500

So v = 250 km per hour

By definition, light travels at the speed of light. About 300,000 kps