How Does Acceleration Affect Perceived Gravity in Space?

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vrghost
On the way into work this morning, happily reading my book (Leviathan Wakes, would suggest it to any sci-fi space opera fan) and there was a passage that read along the lines “they reduced acceleration to sustain a 1g force during the meal” or something along those lines. Its something you often read in books where authors have decided that future spaceships will use acceleration to generate gravity, and clearly that is an option.

So ignoring all the engineering factors, humanity has access to the anti super kung-fu kickass particle that can provide loads of energy indefinitely and they got an engine even more kickass than Chuck Norris. Actually, it is so cool that it can deliver 10 CNU (Chuck Norris Units). Also to have something to work with, from standstill, 1 CNU will provide acceleration equal to 1 G.

Also, to start with, we say that gravity from planets have no impact at all, and that no power is required to sustain speed (will get back to this later)

With these rather general statements, and I am sitting completely still in the space, and I decided to generate 1 G so I could drink my coffee comfortably, I just turn up the power to 1 CNU. But my question is, would 1 CNU of energy continuously give my spaceship 1 G, or would I have to increase the power as my acceleration increases. If the later, would this be just as I am approaching the speed of light, or would it be noticeable pretty much instantly?

The next questions (the ones I said I would get back to) is, would it be true to say that in space, ignoring the occasional particle, would an object accelerated sustain its speed indefinitely or does my ship have to use some of its energy to sustain the speed?

Last question, does the speed of an object impact the amount of gravitational pull an external object will have, so let's say I am going close to a moon, will the amount of pull differ if I am doing it at 0.01 c or 0.1 c
 
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vrghost said:
But my question is, would 1 CNU of energy continuously give my spaceship 1 G, or would I have to increase the power as my acceleration increases. If the later, would this be just as I am approaching the speed of light, or would it be noticeable pretty much instantly?
Welcome to the forums! From your perspective nothing would ever change. You can continually spend 1 CNU and never have to increase it and never reach the speed of light.
 


Thank you very much Ryan_m_b

Just to confirm, and continuously have one G in my space ship?
Would that also mean that if I crank it up to 2 CNU I would get 2 g in my spaceship?
 


If CNU is a unit of force, yes. For a given design, force and power are usually proportional, therefore you can use a unit of power, too.
The velocity of the spaceship (relative to what?) does not matter, as there is no absolute velocity anyway.

Energy is power multiplied with time. Therefore, you need a certain energy per time to maintain the acceleration.

The next questions (the ones I said I would get back to) is, would it be true to say that in space, ignoring the occasional particle, would an object accelerated sustain its speed indefinitely or does my ship have to use some of its energy to sustain the speed?
You would have some friction from the interstellar medium. But apart from that, the spaceship will keep its velocity (relative to any inertial system) if you do not use any propulsion method.I assume that the spaceship has no access to any other structures (like a railroad in space), otherwise things would be a bit different.
 


Just to confirm, and continuously have one G in my space ship?
Would that also mean that if I crank it up to 2 CNU I would get 2 g in my spaceship?

yes. But that is in the frame [reference] of the spaceship itself. Outside observers willsee different effects.