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[GreatWyrmGold]

Repairs and stuff sound nice.

EDIT: What never to do.

[BigD145]

With most iffy mods I put their parts onto dockable craft so I can undock them and carry on without losing an entire craft. Remove mods and the whole craft with those parts will be deleted.

[GreatWyrmGold]

If you want to come back, Minmus is probably easier. Nowhere near as much fuel needed to lift off. (Heck, you could probably get home with an EVA pack. In theory.)

[Eric Blank]

Sadly, if you used an EVA pack to get home, your kerbal would smack into the ground and die for lack of parachute. There was a mod for giving kerbals parachutes though, I think.

[GreatWyrmGold]

There sure is. That's how Scott sent a kerbal home from Gilly.

[Mini]

Acceleration due to gravity depends on the mass of each object, the (square of the) distance between them, and the gravitational constant.

The acceleration of something due to gravity doesn't change as you change its own mass*, hence why at sea level on Earth acceleration due to gravity is always ~9.8m/s², whether you are skinny, fat, or a bus. So yes, adding an ion engine will slow you down a little (but it's still not suitable for landing softly).

*The force does change, but since force increases proportionally to the mass of the object and the acceleration due to force decreases proportionally to mass at the same rate it cancels out, leaving the same acceleration.

[LoSboccacc]

lotsa confusion here, time for explaining.

gravity force depends on your mass, say: forceg = constant * mass

gravity acceleration, on the other hand, follow the acceleration rule: acceleration = force / mass

so accelerationg = constant * mass / mass = constant

acceleration is constant

what happens when you add mass? to the force of gravity: it increase. to the acceleration: it stay the same.


why does terminal velocity increase?


because air drag is a force. terminal velocity happens when forceg = forcedrag

at that point acceleration = (forceg - forcedrag)/mass = 0, terminal velocity = no acceleration (assuming you are falling straight down here)

for a bus, forceg is very big even if acceleration doesn't change. for a person, forceg is smaller, even if the acceleration without drag stay the same.

but!

98kg person: acceleration = (98 - forcedrag)/10

980kg bike:  acceleration = (980 - forcedrag) / 980

see what's going on? you need much more drag to reach terminal velocity with a massive object

that mean you have to go faster to cancel out the force of gravity.

so, the more massive you are, the bigger you terminal velocity will be - no change in gravity constant neither in the acceleration by the force of gravity.

it's simpler: you need more force to slow you down and the force here is drag which depends on speed.

Spoiler (click to show/hide)

anyway, drag in ksp if funny so depending on the engine weight you might get slower because broken physics.

[TheBronzePickle]

Keep in mind, though, that that the larger the object is, the greater the drag because there's more surface area for the air to cling to, which can be yet another variable that causes a difference in terminal velocity.

[ank]

Keep in mind, though, that that the larger the object is, the greater the drag because there's more surface area for the air to cling to, which can be yet another variable that causes a difference in terminal velocity.

But not in KSP.
In KSP drag and size is not related at all. In fact all fuel tanks, no matter the size, has the same drag.
Ion drives have the same mass and drag as an empty FL-T400 fuel tank. While an FL-T800 has twice the mass and the same drag.

So depending on your current ship's mass/drag ration, the ion engine will either slow you down, or make you speed up.

it's simpler: you need more force to slow you down and the force here is drag which depends on speed.

It depends on speed AND drag-coefficient

[TheBronzePickle]

If you're going off the 'drag' number in the parts list, that's not entirely accurate. An orange tank and a tiny puddle-jumper tank both have the same drag per surface area, but even the base game bothers to actually care about that surface area. With a mod focused on making aerodynamics more realistic, like FAR, you can notice an even greater difference.

Of course, I haven't played in a while, so I might be wrong for lack of newer developments, but I don't think the game's creators would backtrack like that.

[GreatWyrmGold]

Acceleration due to gravity depends on the mass of each object, the (square of the) distance between them, and the gravitational constant.

The acceleration of something due to gravity doesn't change as you change its own mass*, hence why at sea level on Earth acceleration due to gravity is always ~9.8m/s², whether you are skinny, fat, or a bus. So yes, adding an ion engine will slow you down a little (but it's still not suitable for landing softly).
*The force does change, but since force increases proportionally to the mass of the object and the acceleration due to force decreases proportionally to mass at the same rate it cancels out, leaving the same acceleration.

I meant force, my bad. Of course, technically acceleration depends on those things too. After all, increasing the mass of the smaller object means that the larger object is moving towards the smaller object a little faster, doesn't it?

[Descan]

Negligibly.

[LoSboccacc]

Acceleration due to gravity depends on the mass of each object, the (square of the) distance between them, and the gravitational constant.

The acceleration of something due to gravity doesn't change as you change its own mass*, hence why at sea level on Earth acceleration due to gravity is always ~9.8m/s², whether you are skinny, fat, or a bus. So yes, adding an ion engine will slow you down a little (but it's still not suitable for landing softly).
*The force does change, but since force increases proportionally to the mass of the object and the acceleration due to force decreases proportionally to mass at the same rate it cancels out, leaving the same acceleration.

I meant force, my bad. Of course, technically acceleration depends on those things too. After all, increasing the mass of the smaller object means that the larger object is moving towards the smaller object a little faster, doesn't it?

No.

The force is bigger, but has to accellerate more mass so it evens out

[IronTomato]

Duna Expedition Thing continues to progress. I did my orbit-completing burn way too late, and ended up wasting a ton of fuel. Still, the thing managed to get to Duna, though I was forced to give up after that because I was unable to land properly due to the fact that I had forgotten landing legs. At least I got a taste of what the thing can do.

[GreatWyrmGold]

No.

The force is bigger, but has to accellerate more mass so it evens out

There are two equal forces: The force of object a on object b, and the force of object b on object a. I was talking about the second. If b is twice as massive as a previous b, the acceleration from the first force will be the same, but the acceleration from the second will not be.

Read carefully to figure out what I'm actually saying.