If we have spacecraft, capable of accelerate 3G for unlimited time, how long it take to reach near speed of?

Question

LIGHT?

Just teoreticly. Someone says it never be possible to go to space with hommade spacecraft..:-)

Answer 1

Albert said it, you can't get there from here. Let's assume you have the infinite power source you will need to push the near infinite relativistic mass you have as you approach the speed of light and you are deep space with no air friction or other forces to worry about, in other words, the ideal (but impossible) case.

Velocity is acceleration times time. Light travels at 186000 miles per second. One Gravity is 32 feet per second squared. So, we work backwards from the desired velocity and doing unit conversion from miles to feet . 186000=96/5280*T
The answer is 186000*5280/96 which is 10,230,000 seconds, which at 86400 seconds per day means 118.4 days.

Which does not sound nearly long enough...

Answer 2

One G is about 10 meters per second every second, or 0.01 kilometers per second every second. So every 100 seconds at 3G adds 3 kilometers per second to your speed. Since the speed of light is 300,000 kilometers per second, you might think that 10,000,000 seconds (about 4 months) would get you to the speed of light, but you would be wrong. According to relativity, you could accelerate at 3 G forever and never get to the speed of light. In relativity, 1+1 does not always equal 2. It has nothing to do with technology, it is the physical nature of the universe that makes the math of speed change on you to thwart any attempt to go faster than light. The source has the mathematical details, but it is not easy to understand. Basically, as you move faster, time and space change so that you see yourself still accelerating at 3G while at the same time another person standing still sees you as hardly accelerating at all. To you, traveling at near the speed of light, time slows down, the universe gets smaller, and you seem to be going slower than light but still getting to distant galaxies in a few years. But when you stop at a distant galaxy, you find that millions of years have passed and you have really been traveling for millions of years and not one year. When you go back to Earth to tell your friends about your trip, they are all long dead because it is millions of years later on Earth, even though you think you were only gone a couple of years.

Answer 3

It'll never happen, laddie. For every increase in velocity there is a manyfold increase in the demand for fuel. No vessel could possibly carry with it the amount of fuel needed to propel it to anywhere near the velocity of light...even a vessel the size of the planet Earth. Don't forget, besides the weight and inertia of the vessel, there's the considerable weight of the fuel supply. You'd burn most of it just getting your vessel up to escape velocity, as is the case with all space vehicles we have now.

Answer 4

I am really not sure. However!!!!! As one very prominent Quantum Physicist puts it; "All we know, or think we know about science, is at best "JUST A GUESS".
Considering that scientists are froever changeing their story to fit new findings, we can't say for sure (an absolute fact) what will be in the comeing future. What we know right now, isnt always going to be the same at a later time.
For all we know, we may have already made that journey.