If you turn on a flash light while driving a car does it break the speed of light barrier?

Question

Please be truthful not mean. I'd like dignified answers.

Answer 1

If you're in an airport, and standing on a moving sidewalk that's travelling at 5 mi/hr, and you start walking at 4 mi/hr in the direction that the sidewalk is moving, you will then be travelling at 9 mi/hr. Light is not like this i.e. its speed is not additive. This would mean that if you were standing on a bridge over some railroad tracks one evening, and were watching one train heading in your direction and another train, with a caboose, heading away from you on parallel tracks, as the two trains passed each other, the light from the caboose would reach your eyes at the same time that the light from the headlight of the train approaching you hit your eyes. Another thing, is that light always seems to travel at the same speed regardless of the velocity of the observer. To use a train example again, if you were seated in a passenger car of a train that was stopped on tracks that ran parallel to a highway, and an automobile were to pass the train at 75 mi/hr, it would obviously appear to you to be moving at 75 mi/hr, and would pass the train fairly quickly. If the train were travelling at 50 mi/hr, the automobile would appear to you to be travelling at 25 mi/hr, and it would take three times as long for it to pass the train.
On the other hand, if it were possible for you to travel at immense speeds in some sort of spaceship, racing a beam of light, the light passing you would always appear to be moving at the same speed. This would be because, for you, time would be slowing down. If you could take a ride on this vessel at near the speed of light, you could return to earth after 40 years had passed here having aged very little. The idea that the speed of light is constant, but that time is relative is mind blowing, isn't it? I can't even begin to understand the genius of someone like Albert Einstein.
Forgive me, I'm no expert on this subject, and hopefully another respondant will make any needed corrections or clarifications to what I've written, and will be able to direct you to some good reference sources.

Answer 2

It's kind of interesting how light works. When James Clerk Maxwell did his experiments with electricity and magnetism in the late 1800's, he was able to predict that there would be such a thing as an electromagnetic wave.

Accelerating electrical current creates an accelerating magnetic field which creates an accelerating electrical current, etc, etc, etc. Based on his lab experiments, Maxwell was able to predict what speed these electromagnetic waves should travel at. Not coincidentally, it was exactly the same as the speed of light which had been independently measured by astronomers.

Now Albert Einstein's theory of relativity said that for two observers moving relative to each other, the laws of Physics should be experimentally the same. This means that if a different scientist on some other planet across the universe (moving at half the speed of light relative to earth) perfomed Maxwell's experiments, he would come up with the same speed for electromagnetic waves.

Now since all observers come up with the same number for the speed of light, it creates strange predictions for time and space when stuff starts travelling near the speed of light.

Suppose 2 space ships leave earth at the same time. Both are travelling at 0.9 times the speed of light in opposite directions. An observer on earth will see each spaceship travelling away at 0.9 times the speed of light, and an observer on either of the ships will see the earth moving away at 0.9 times the speed of light.

However, an observer on one of the ships will see the other ship moving away at about 0.99 times the speed of light.

Not very intuitive is it? All the other stuff about time shifting is even more interesting, but it requires more space than I got here to explain it. Check out the links. There's tons of good info in them.

Answer 3

What is interesting is that you are worried about the velocity of your car. You are traveling through the universe at around 300 km/s. That is 1/1000 th of the speed of light. The car does .03 km/s. If there was a stationary observer, as our solar system whipped past, he would see a spectral shift in your flashlight as you went by. But, he would measure the speed of the light from your flashlight the same, from in front of you and after you went by.

The earth itself does some 30 km/s around the sun. So don't worry about the car, you are already going faster than man has ever gone, Helios solar probe hit 74 km/s.

Answer 4

no, it doesn't. Light is the universal speed limit. Due to the rules of relativity, we cannot add two velocities by just...adding them. Because light (by definition) goes at the speed of light, it doesn't matter where you are watching the light from -- it could be from inside the car or outside of the car -- you will ALWAYS measure the light to be c. This is one of Einstein's most groundbreaking theories. It has been tested extensively, and there is no doubt among physicists that this is a fundamental fact of our universe.

Answer 5

No.

The speed of the light will be the same. This result is unexpected, but was observed first at the end of the 19th century.

It was used as an axiom by Einstein to construct the theory of special relativity (contrary to other answers which say it is a prediction of relativity - it is not, it is the reverse).

Answer 6

The light is still projecting at the same rate (whatever the "speed of light" is). The originating source of the light is still a flashlight in a car and this remains constant regardless of the motion of the car.

Answer 7

The speed of light is independent of the speed of the source. No barrier breaking here.

Answer 8

Well, my jet can go really fast . ... ! The car moves at about 1/4 that speed--using regular fuel. Unfortunately, the distance that I cover never quite makes the pace.

Answer 9

Well, it should cos logically it's speed of light + the speed of the car.

Answer 10

NO. YOU ARE STATIONARY RELATIVE TO THE LIGHT SORCE.