# Question about space travel and the human body

1. Aug 7, 2014

### Keith

Hello I have a question that's been bothering me for a while now and I figured I'd post it here to see if anyone could put my mind at ease. (Sorry if I accidentally posted this in the wrong place)

Given that people can only withstand a certain amount of force on their bodies (about 5 Gs), would the amount of time that it would take to reach (near) the speed of light exceed the length of the average life expectancy? In other words, is it possible for a human to accelerate to (and decelerate from) the speed of light within a lifetime without experiencing more than 5 Gs of force?

Last edited: Aug 7, 2014
2. Aug 7, 2014

### Staff: Mentor

That's something you should be able to calculate for yourself. How many seconds does an average person live? How much is 5G, in meters per second per second? If you completely ignore relativistic effects, what speed would resulting from accelerating at that rate for a lifetime? How does this compare with the speed of light?

If it's close, you would have to go back and do the relativistic acceleration calculation to be sure. But if it's not even slightly close, you'll have your answer. Try it and see what you get....