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Unless the person has excellent balance, they would fall over in a frictionless environment. It would be like walking on ice with smooth polished shoes except even more slippery - there would be no friction at all.

Since the coefficient of friction 'u' would be zero, it would be impossible for the force of friction to move a person anywhere, which means, no walking. Movement would have to be produced by pushing against something.

Interestingly enough, it would be possible to change the direction that one was facing without needing to act on an outside body.

It involves rotating the lower body while the arms are spread out as wide as possible, to increase to moment of inertial, and then pulling the arms in as close as possible in and extending a leg to increase lower body's moment of inertia, and then rotating the upper body.

This is also exactly how a cat can change orientation in mid air.




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