Re: What is the error in my calculation?


"Ronald RNR" <RRNR@xxxxxxxxx> wrote in message
news:e6kar8$dqo$1@xxxxxxxxxxxxxxxx
I want to make a faster then light spacecraft so i can go vistit
those new planets.

I have learned about g = 9.81 m/s^2.

So to reach light speed, with a comfortable chair, with
my own weight, I need to acellerate 300,000,000 / 9.81 = 30581039.76
seconds. This is 8494 hours, and that is 352 days, say 1 year if I
take it easy.

And 1 g is not that much, does not take a string engine.

I have not decided on the fuel yet, maybe one of those reactors will do.

I've been pondering your little dilemma for some time and, ignoring
relativistic effects, I really can't see how you can accelerate
yourself from zero to light speed.

If you carry with you a fuel mass which makes up half the entire
mass of your spacecraft and that fuel mass can be converted to some
form of energy that can be expelled at light speed, when the fuel
tank is empty, your spacecraft will be traveling at only half light
speed relative to your place of departure. That's probably more
evident picturing the spacecraft mass as being split into two equal
parts and driven away from each other at light speed in a single
action.

It may seem that the next halving of your already halved rocket mass
will push you up to light speed relative to your destination. But
that can't be. The only possible remaining rocket mass is then zero.
If the initial jump from zero to light speed is made in a single
action any remaining rocket mass will shift the fuel mass to some
degree, rendering the light speed goal still unreachable.

Anyway, something seem to be wrong, probably with my reasoning.

-----

Max Keon



.

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