Physics space question...

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Octopus
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Physics space question...

Post by Octopus »

So you're in a small ship (a pyro maybe) and you're ejected into space by a mother ship (like a battlestar). Your small ship doesn't need to apply any force on take off, because the mother ship is made to push you out at super sonic speed. Since we're in space you could keep that momentum until you crash. But you have thrusters to steer your ship. Could you keep that momentum as long as you steered L,R,U, and D? Or would that slow you? How about going in circles?
shaktazuki
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Re: Physics space question...

Post by shaktazuki »

Octopus wrote:So you're in a small ship (a pyro maybe) and you're ejected into space by a mother ship (like a battlestar). Your small ship doesn't need to apply any force on take off, because the mother ship is made to push you out at super sonic speed. Since we're in space you could keep that momentum until you crash. But you have thrusters to steer your ship. Could you keep that momentum as long as you steered L,R,U, and D? Or would that slow you? How about going in circles?
As long as you applied no thrust even obliquely against your inertial vector, you won't slow down relative to the mother ship. Try it and see! :P
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Octopus
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Post by Octopus »

But wouldn't turning in circles be doing that?
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Post by Wings »

If you went down after being ejected, you'd be going diagonal from the starting point, same with left or right. It wouldn't work like flying a jet. The only way to go straight left, or straight down, or straight right would be to slow down first.

Haha, if space battles in movies applied actual physics they'd be really weird, if something could always thrust, then it would be accelerating constantly, and it would take forever to turn to another direction, thus not being maneuverable at all.
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Post by Octopus »

Sorry. I mean to steer while rotating.
I got my answer from a physics major. But thank you all anyway!
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Post by fliptw »

you don't steer a craft like a pyro or starfury(probably the best example for this) like you do a car - you don't steer, and you never slow down unless a force acts about the craft in the direction your are currently traveling in.

if you where shot out at the moon, and used your thrusters to make the ship spin on a given axis, you are still heading towards the moon. Until you fire your thrusters towards the moon, you never slow down wrt to your movement towards the moon.
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Post by Octopus »

fliptw,
I see what you're saying. Please understand that I worded my original post badly and I apologize. Thank you for your post.


You all are very knowledgeable people and I'll communicate my questions better moving forward. Thank you! :)
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Post by Tricord »

In the absence of forces, an object (ship) follows what we call a geodesic, which is \"the shortest path between origin & destination\". When there is no mass (and thus no gravity and no space-time bending) this is a straight line. However, in the presence off mass (i.e. a planet) this geodesic can bend and could become a circle (or ellips) as is the case for satellites in geo-stationary orbit around earth.

If you want to fly in a circle without orbiting around a planet, you will need a constant force that constantly changes in direction. Basically, it is one of the most energy-inefficient trajectories because you continuously have to adjust away from your geodesic pathway.

Hope this clarifies :)
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Post by Dedman »

It's all about vectors baby!
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