why does a razor blade placed on the water surface move away from a charged body?
I didn't know it did. Can you give us a pointer to a reference that discusses this experiment?
could be due to eddy currents
Never heard of it. But..
A charged body near a conductor will induce a surface charge, distributed so that there is zero electric field within it (this is similar to dielectrics, and should very weakly attract the conductor, in the absence of other effects). Such a distribution always has to be concentrated at any points or edges (compared to flat surfaces), and so the highest charge density (and strongest electric field) should occur along the razor blade. This most likely transfers charge to water molecules there, or at least raises the water pressure near the blade (dielectric fluid prefers being near high charge density), floating the razor blade in the opposite direction, but that's a bit of a guess.
guys hasn't any idea on this?
As I said, it would help a lot if you could list a credible source for this claim, so that we can go read about it and help to explain it to you. Without a credible source for us to look at, it is unlikely you will get much more than wild guesses.
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