2007-12-19 09:31:07 · 6 answers · asked by loops 1 in Science & Mathematics ➔ Physics
f = m*a (force = mass * acceleration) or a = f/m
Since light has no mass, it has infinite acceleration.
2007-12-19 09:34:37 · answer #1 · answered by HooKooDooKu 6 · 0⤊ 4⤋
This is an excellent question.
Some have answered that light speed is constant, e.g., v = c. But that is not entirely true. Light speed is fixed, but only in a given medium and only of not tampered with by scientists.
In fact, light speed in water, for example, is different than light speed in air. This is why a pencil seems to break or bend where it enters a glass of water. That is, the light speed is slower in water than in air.
In fact, light in any medium is typically and normally slower than in a vacuum or air, which is almost the same as in a vacuum. So when a photon emerges from one medium into another one, there is acceleration or deceleration, as the case may be.
By altering the medium in which light travels, scientists have actually brought light to a stop. [See source.] Bottom line, light does accelerate/decelerate, but it's not instantaneous because light does have momentum p = hf/c; so changes in velocity do not occur instantaneously.
2007-12-19 17:52:40 · answer #2 · answered by oldprof 7 · 0⤊ 0⤋
It is never at 0. It is always at 3 x 10^8.
Its like any other wave. A sound wave does not magically speed up from zero to the speed of sound. It is a disturbance that always propogates at the speed of sound.
2007-12-19 17:39:42 · answer #3 · answered by Anonymous · 1⤊ 1⤋
light has no mass therefore nothing interfears with its speed so that its speed is always constent
2007-12-19 17:40:38 · answer #4 · answered by Bill 2 · 0⤊ 1⤋
speed of light is a constant
2007-12-19 17:36:21 · answer #5 · answered by FutbolFan2147 5 · 1⤊ 2⤋
There is no acceleration.
2007-12-19 17:37:32 · answer #6 · answered by johnandeileen2000 7 · 1⤊ 1⤋