Question
Mon September 24, 2012 By: Nevin

sir/madam

Expert Reply
Mon September 24, 2012
radius of drop =  r = 10^(-7) m
let the volume of the drop be: V = 4/3 (pi) r3 cu.m
thus mass of drop: m = pV
p = density of water
and g = gravitational acceleration
charge on drop: q = 1.6 x 10-19 C
thus force on drop: F = qE where E is the electric field
this should be enough to balance its mass:
 
F = mg
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