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Alouette
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Homework Statement
In an ink-jet printer, drops of ink are given a controlled amount of charge before they pass through a uniform electric field generated by two charged plates. If the electric field between the plates is 1.5x106N/C over a region 1.20cm long, and drops of mass 0.12nanograms enter the electric field region moving horizontally at 16m/s.
What is the vertical deflection between the point where it leaves the plates and where it strikes the paper, if the paper is 0.50cm from the end of the charged plates? Ignore other forces such as gravity and air resistance, and assume the field between the plates is vertical and constant, and drops abruptly to zero at the edge of the plates.
Homework Equations
a = F/m = qE/m
t = (.012)m/(16) m/s = 7.5x10^-4
Vertical velocity [Vv] = at
D = Do (starting displacement at end of plates) + (Vv*t')
The Attempt at a Solution
I found q to be 1.42x10^-16. and a turns out to be 1775. So Vv = a*t = 1.33
Then t' = (.50) cm/ (16) m/s^2 = 3.12x10^-4
Then multiplying Vv(t') and adding to Do, I got 9.16x10^-4 but this is wrong.
What have I done wrong? I followed the formulas didn't i?
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