In an inkjet printer, letters and images are created by squirting drops of ink h

Question

In an inkjet printer, letters and images are created by squirting drops of ink horizontally at a shoot of paper from a rapidly moving nozzle. The pattern on the paper is controlled by an electrostatic valve that determines at each nozzle position whether ink is squirted onto the paper or not. The ink drops have a mass m = 1.00 times 10^-11 kg each and leave the nozzle and travel horizontally toward the paper at velocity v = 21.0 m/s. The drops pass through a charging unit that gives each drop a positive charge q by causing it to lose some electrons. The drops then pass between parallel deflecting plates of length D_0 = 1.95 cm, where there is a uniform vertical electric field with magnitude E = 7.60 times 10^4 N/C.(Figure 1) If a drop is to be deflected a distance d = 0 320 mm by the time it roaches the end of the deflection plate, what magnitude of charge q must be given to the drop? Assume that the density of the ink drop is 1000 kg/m^3, and ignore the effects of gravity. Express your answer numerically In coulombs.

Explanation / Answer

Time taken by drops to pass through the slits, t = D0/v

t = 1.96x10-2/21

t = 0.933x10-3 s

t = 0.933 ms

And acceleration of drops along the direction of electric field, a = F/m

a = qE/m

a = q(7.6x104)/1x10-11

a = (qx7.6x1015) m/s2

And hence deflection

0.320x10-3 = vit + at2/2

0.320x10-3 = 0 + (qx7.6x1015)(0.933x10-3)2/2

q = 0.09674x10-12 C = 96.74x10-9 C.

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.