2007-01-17 02:13:49 · 9 answers · asked by Mandar 2 in Science & Mathematics ➔ Physics
Laser beams are different from light beams because the light molecules all line up in the same direction. In a flashlight, there is a wide circle where the light goes in different directions, but a laser beam will travel [almost] perfectly straight. Light as well as laser beams can travel indefinetly, so if you point a laser into space, it will go on through space until it hits something.
2007-01-17 02:18:45 · answer #1 · answered by Phoney baloney answers 2 · 3⤊ 2⤋
Any light source will produce light that will travel forever until stopped by something. In outer space this means hitting an object (eg a planet) or getting absorbed by interstellar dust - in any event, a long way.
On Earth it will be absorbed by the atmosphere eventually.
By the way, although a laser beam is relatively collimated, it is absolutely not the case that the beam does not spread out. That would take a laser of infinite size. In reality, a typical laser would project a spot maybe 50m across if shone at the moon. Smaller lasers with smaller apertures will produce a beam that spreads more. This is a fundamental optical property of light.
2007-01-17 02:52:22 · answer #2 · answered by Anonymous · 1⤊ 0⤋
In space- for quite a long way. Possibly millions of miles before the small amount of dispersion effects at the start make the once point light source wide enough such that it's not significant.
If we're talking about a little laser pointer here on earth, in the earth's atmosphere, there's plenty of dust and particulate matter in the air that will disperse the beam- generally within a few hundred yards. Maybe a mile for a better laser.
2007-01-17 03:23:37 · answer #3 · answered by Morey000 7 · 0⤊ 0⤋
Laser is an electro magnetic radiation.
All electro magnetic radiations travel in vacuum with a speed of 3x10^8m/s.
The do carry energy.
Their speed is reduced ONLY when they enter into a medium.
Their speed is regained to 3x 10^8m/s, when they leave the medium and enter again vacuum.
Vacuum does not absorb energy.
Some of the energy is absorbed when they travel inside a medium other than vacuum. The rest of the energy is transmitted as E.M radiations.
If all energy is absorbed by matter, there is no energy in the form of EM wave (light).
In the light of the above points, review your question.
Your question becomes unfortunate.
All electro magnetic radiations travel to infinite distance and for indefinite time.
There is nothing special in laser beam.
Light from distant stars WHICH ARE NOT LASER reaches us after millions of year.
But for absorption, light from a match stick will travel infinite distance and for indefinite time.
2007-01-17 12:20:00 · answer #4 · answered by Pearlsawme 7 · 0⤊ 0⤋
that would depend on the intensity of the laser.most pen-like pointing lasers don't travel far
2007-01-17 03:04:32 · answer #5 · answered by Tharu 3 · 0⤊ 0⤋
It will travel forever, until something blocks the path.
2007-01-17 02:22:23 · answer #6 · answered by jenn 2 · 2⤊ 0⤋
i have to correct the 1st post. speed of light is not in seconds squared...in imperial units the speed of light is 186,282.397 miles per second...
2007-01-17 02:26:02 · answer #7 · answered by Beach_Bum 4 · 1⤊ 0⤋
If there is nothing to stop it, light will travel to infinity at a speed of 186,000 miles per second squared.
2007-01-17 02:18:28 · answer #8 · answered by abgroove 2 · 1⤊ 4⤋
Quote from above:
"This is a fundamental optical property of light."
No, this is a fundamental property of all energy and matter. Please see the uncertainty principle.
2007-01-17 04:08:05 · answer #9 · answered by Patrick M 2 · 0⤊ 0⤋