HaplessBystander

What I'm taking away from this is I've failed to account for the relative velocities between the ship and the propulsion unit and the faster the propulsion unit is ejected the more kinetic energy it will have to impart to the ship to produce the same delta-v. Will the aforementioned additive approach still work if the equation is altered to account for this? If so, how do I alter the equation to make it work? If that wasn't the intended takeaway, I'm lost.

Regarding nuclear pulse propulsion, the idea of it, by my understanding, is to convert the nuclear potential energy of the propulsion units into kinetic energy for the ship. So, if you know the amount of kinetic energy successfully imparted to the ship by a propulsion unit and mass of ship you can find the delta-v imparted to the ship by that propulsion unit as per the equation v=sqrt(2KE/m), right? If the rocket equation is not applicable to NPP ships then my only thought to find the ship's delta-v budget is to add up the delta-v provided by each propulsion unit, accounting for the changing mass of the ship as each propulsion unit is expelled. So, the equation would then be: Where: E_K is the kinetic energy m_wet is the ship's wet mass n_units is the total number of propulsion units and m_units is the mass of each propulsion unit That's what makes intuitive sense to me, anyway.

Been thinking about nuclear pulse propulsion rockets lately. Wanted to know, is the mass flow rate the mass of all bombs detonated per second or is it just the mass of the tungsten propellant (as per the Project Orion design) in all the bombs detonated per second? As I understand, the mass flow rate times the exhaust velocity equals the force exerted by the engine, so I want make sure I'm using the right value for the mass flow rate. Also, if you're aware of any valuable equations specific to nuclear pulse propulsion rockets (that aren't too complicated for a layman) please do share.

That's all very well but what I really need to know is just why that little prime symbol is there. It's specifically the calculus used in this math I don't understand

I have an inquiry regarding how to find the theoretical maximum exhaust velocity of a relativistic rocket. I was able to find a document that provides an equation at the very bottom to do just that, but stops short of explaining the logic behind the equation: http://www.relativitycalculator.com/images/rocket_equations/AIAA.pdf Someone else had the same question: https://physics.stackexchange.com/questions/514616/maximum-exhaust-speed-of-relativistic-rocket?answertab=votes#tab-top The provided answer is very helpful! But, there's still, owing to my lacking some of the mathematical knowledge assumed on the part of the answer provider, a gap I was hoping you all of the fine Kerbal Space Program Forums would be able to fill in for me. So, two questions: 1) Why is the velocity of the rocket post-burn a derivative " dv' "? Isn't the derivative of a velocity with respect to time an acceleration? 2) What, exactly, are the steps taken to get from the first equation to the second? I know that it states two of the steps, but the major tripping point is I've no idea what's being referred to by "O(dx^2) terms." Thanks for the help y'all.

Wait, you can get away with an entire meter per second^2 acceleration rate before crew members start to experience slanted gravity? That's ten times the maximum acceleration rate I'd been under the impression was maybe, possibly low enough to not cause problems

I'm aware of the concept of a gimbaled centrifuge habitat. What I'd like to know is, at what rate of acceleration does gimbaling become necessary? Is there a sweet spot where your ship's acceleration rate is low enough that your habitat section doesn't need gimbaling (and can thus be shaped as a simple ring) but high enough to support crewed expeditions to Mars or the outer solar system in a reasonable time frame?

Hello, I wanted to ask about the idea of constant acceleration space ships with rotating habitat sections (like The Hermes from The Martian). How fast would it be possible to accelerate such a ship before the vector of the two forces starts to mess with the crew's perception of gravity? Clearly it would be a small acceleration (the Hermes accelerates at two millimeters per second per second), but how small? It would seem the answer depends on just how little linear acceleration it is possible to perceive. My current understanding is that accelerations greater than one centimeter per second per second may be perceptible to some people and accelerations greater than ten centimeters per second per second will be perceptible to most people. So, if you want to make sure the crew is comfortable you should stick to the lower end of that range, maybe two centimeters per second per second. Is that right? Or is that acceleration rate already too high?