Gravity and angular momentum

1. Aug 21, 2004

mee

Is angular momentum a push and gravity a pull? I just thought there might be unforseen differences in human reaction on a spinning space station.

2. Aug 21, 2004

arildno

On a spinning space station far away from hugely massive celestial bodies, gravity can be neglected as a force.
You will be pushed outwards towards the outer shell of the station by the centrifugal force (a pseudo-force); the normal force from the shell will keep you in place.
In effect therefore, it is the centrifugal force which will play the role of gravity.

The most apparent discrepancy between life-on-earth and life-on-space-station will probably be effects from the Coriolis force (another pseudo-force)

3. Aug 22, 2004

mee

Thanks but this doesn't answer my question.

4. Aug 22, 2004

arildno

Since "angular momentum" in this context doesn't make much sense, try to elaborate on what you meant.

5. Aug 22, 2004

mee

I have been told emphatically that there is no such force as centrifugal force and to use the phrase angular momentum when referring to what it referrs. Centifugal force then. Centrifugal force seems like a pushing force and gravity seems like a pulling force. Would there be any subtle differences on physiology in a spinning space station if one is being "pushed" rather than pulled. like the space station in 2001.

6. Aug 23, 2004

ArmoSkater87

You are right, centrifugal force doesnt actually exist, its only an effect that gives a force outward. Since all objects in motion want to stay in motion in a straight line...the constant spinning and changing in direction causes an outward "force". Angular momentum is what is actually present, the system of the planets orbiting around the sun is a balance between gravity and angular momentum. As for the space station...using artificial gravity in space stations solves the problem of decaying muscles, but would not help in the case of decreasing calcium in the bones. In other words, its not as good of an environment as gravity on earth.

7. Aug 23, 2004

pervect

Staff Emeritus
I gather that the coriolis force is a problem if the space station is too small. There's no difference between gravitational acceleration and inertial forces per se, the difference is that in the space station you have the coriolis force as well as the centrifugal force.