Interesting question indeed. I have always seen psionics--Telekinesis as a mental rope connecting the Psion to the object they are trying to move. First if the Psion tried to move the 10 kg object in a gravity field the gravity field would "hold the Psion down". In a no-gravity arena I believe that both the object and the Psion would move. A level one Psion would move at a rate on one meter per combat turn and the object being one tenth their weight would move ten times as fast. Your Psion could also use his skill to push an object away to alter their course. Also I would have the Psion make a willpower skill save to find his center (forgive: I'm drawing on my martial arts experience and lifeguard training here). What you are saying is most defiantly a panic ridden scenario (saw Gravity yesterday) and people have a tendency to loose their higher thinking and their animal instincts take over, hence the willpower check.
Roger
Roger