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

1. Jan 5, 2012

### lamp23

If u stand on top of a spaceship, u will not be thrust backward?
U only do on top of an airplane cuz 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?

2. Jan 5, 2012

### rcgldr

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

3. Jan 5, 2012

### silverdiesel

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.)

4. Jan 5, 2012

### rorix_bw

1 - Top?

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

3 - Yes

4 - Down?

5. Jan 5, 2012

### Rush2112

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.