Question

An unsecured astronaut is floating in deep space. He switches on a hand held drill. The drill bit begins rotating clockwise with high angular velocity. Describe what happens to the astronaut- drill system and explain why.

Answer 1

An equal amount of rotational force is applied to both the drill head and the astronaut. Having a greater mass, the force has less noticeable effect on the astronaut, but he will rotate around the drill in the opposite direction.
This is defined by newtons 3rd law "for every action there is an equal and opposite reaction". On earth, this reaction has little effect. you might feel your hand twist slightly as you switch on the drill. In space, there is no resistance with which you can damp the rotational force imparted upon you, therefore you rotate.