HELP.!!! A razor blade is placed gently on a water surface. A charged body brought brought near the razor?

Question

Razor Blade
A razor blade is placed gently on a water surface. A charged body brought near the razor makes it move away. Describe the motion of the razor if an external electric field is applied.

Answer 1

I do not think so.

When you bring a charged body near the blade, there is induced charge in the blade such that the surface near the charged body is charged with opposite charge (bound charge) and the surface opposite is charged with the same charge (free charge). Since the water is conducting the free charge moves away, so that there is only bound charge left on the blade, which is opposite to that of the charged body. Hence, the blade should in fact be attracted towards the charged body.

Now coming to the second part of your question.
when you apply an electric field then the same phenominon of charge induction will occur, however, the charge will not flow to ground as both side will be bound charge. However, some edges of the blade will be sharper and will have higher charge concentration on it. These sharp parts will align in the direction of the electric field. So, the blade will move and align itself to the direction of the electric field.

Answer 2

razor blades dont float