Originally Posted By: paul
the opposing accelerator is removed after the masses are accelerated slightly as I mentioned earlier.

So it accelerates them just enough to feed them into the main accelerator at the same rate other masses are leaving it, so as to maintain 20 in the main accelerator at all times?


No , you dont decelerate the mass .... the mass is only changing direction.

Yes only changing direction, and that requires a force, which can be done just by letting it fly through a U-shaped pipe, or hitting a spring. No need to put any energy in.

Originally Posted By: Kallog

To a physicist, 'acceleration' includes a change in speed or direction. Look up wikipedia to get a more thorough picture. This is the same acceleration in F=ma so it's crucial that we use a consistent definition.

I have a clear understanding of that , and physicist also use decelerate to describe using a force to decelerate a object.

picking at straws are we?


No , we do not apply any force while the mass moves through the U turn.

We/mass/tube/etc. Somehow there's a force, as you say, and that's what I mean too. We don't need to fire up another rail gun or anything.


the mass itself applies a force to the U turn and that force is its mass * velocity

I ignored this before because it didn't really seem to matter, but now we better straighten it out:
F=ma, F<>mv, p=mv.


knowing that the masses passing through the turnarounds cancel
each other out , why do you insist on discussing them?

Because they don't. In this new situation with a slight acceleration provided at the turnaround before the accelerator, we have masses going very slowly through that, while _at the same time_ there are masses going at 39m/s through the opposite turnaround. Different speeds, different forces.

Sure the 39m/s masses eventually get to the other turnaround and apply the same but opposite force there. But by the time the last few of them are doing that, there'll be new, even faster masses that've been accelerated twice, going through the 1st turnaround, so they still don't cancel each other out.

This is why I keep asking for an animation. Even tho it's a bit of work to make, it'll clearly show what's happening without having to consider any forces or momentums. I'm sure you have the programming skills to generate such a thing automatically. I don't want to do it because I expect you'll say I've got it wrong and have to do it again.