Jumping perpendicular out of a fast spaceship will retain your speed right?

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Discussion Overview

The discussion revolves around the physics of jumping out of a horizontally moving spaceship, specifically addressing the retention of horizontal speed after the jump and the effects of forces acting on the jumper. The scope includes conceptual understanding and application of Newton's laws in a space environment.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that if a person jumps up from a horizontally moving spaceship, they will retain the same horizontal speed as when they were inside the spaceship.
  • Others argue that the absence of air resistance in space means that a jumper would not be thrust backward, unlike on an airplane.
  • A participant mentions that to return to the spaceship, one could use thrust (from a jetpack) or a tethered line.
  • One participant asserts that without external forces acting on the jumper, they will continue with the same velocity, referencing Newton's first law of motion.
  • Another participant challenges the notion of absolute rest, suggesting that relative to the spaceship's frame, the jumper would not be moving at 0 mph after jumping out.

Areas of Agreement / Disagreement

Participants express differing views on the implications of jumping out of a spaceship, with some agreeing on the retention of horizontal speed while others contest the concept of absolute rest in space. The discussion remains unresolved regarding the exact dynamics involved.

Contextual Notes

Limitations include assumptions about the absence of external forces and the definitions of speed relative to different frames of reference. The discussion does not resolve the complexities of motion in a vacuum versus on Earth.

lamp23
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If u stand on top of a spaceship, u will not be thrust backward?
U only do on top of an airplane because of air resistance?
So if u jump up out of a horizontally moving spaceship, after you jump out you are moving with the same horizontal speed as you were inside the spaceship? U just have to thrust downwards to get back?
 
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lamp23 said:
So if u jump up out of a horizontally moving spaceship, after you jump out you are moving with the same horizontal speed as you were inside the spaceship? U just have to thrust downwards to get back?
Or use a tethered line to get back. There were four untethered space shuttle space walks where a thruster pack was used to allow the astronaut to move around.

http://en.wikipedia.org/wiki/Extra-vehicular_activity
 
lamp23 said:
If u stand on top of a spaceship, u will not be thrust backward?
U only do on top of an airplane because of air resistance?
So if u jump up out of a horizontally moving spaceship, after you jump out you are moving with the same horizontal speed as you were inside the spaceship? U just have to thrust downwards to get back?

Yes, that is exactly correct. Thinking about space dynamics is the best way to understand F=ma. You will continue to have the same velocity until acted on by some outside force (jetpack, tethered line). Its a bit hard to fully grasp here on earth, because we are constantly acted upon by various forces. (Gravity, pressure, wind resistance, etc.)
 
lamp23 said:
1) If u stand on top of a spaceship, u will not be thrust backward?

2) U only do on top of an airplane because of air resistance?

3) So if u jump up out of a horizontally moving spaceship, after you jump out you are moving with the same horizontal speed as you were inside the spaceship?

4) U just have to thrust downwards to get back?

1 - Top?

2 - Air resistance [STRIKE]and gravity[/STRIKE]

3 - Yes

4 - Down?
 
Mother nature did not endow ur spaceship witth the gift of absolute rest, so yes, relative to the ships frame you will go 0 mph after jumping out of it.
 

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