Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

Suppose engineers built a large circular room in a rotating space station where if one looked directly up from any location, one could see the floor.

If one used a ladder to reach the center of the room, could they balance an object in the center of the room's rotation, such that the object floated unsupported? Would it be easy to place the object there or quite difficult?

share|improve this question
add comment

1 Answer

Assuming the whole space station was moving inertially, whatever gravity field it is in is essentially flat (tidal effects insignificant), you let the object go exactly on the axis of rotation of the space station, and you released it with 0 apparent speed as you observe it inside the room, then yes, the object would would float in place once released.

If the object is small and released not only on the space station's axis of rotation but also its center of gravity, then even tidal effects cancel out.

share|improve this answer
    
As an add-up, it's just the same as if you released the object into the center of Earth, or Sun or whatever ;-) –  Waffle's Crazy Peanut Mar 31 '13 at 15:33
1  
@Crazy: With one big difference which is that the gravity of the earth or sun would be significant, whereas the gravity of the space station itself would be considered insignificant. That's why you could release the small object anwhere on its axis of rotation, but with massive objects (like a planet), it would have to be additionally released at the center of mass for it to appear to float. –  Olin Lathrop Apr 1 '13 at 23:03
    
Would it be rather easy for someone to place the object there or would it be rather challenging and likely fall in one direction if not placed precisely in the correct spot? –  Village Apr 10 '13 at 12:20
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.