Question

Problem 3: Three particles are placed in a line. The left particle has a charge of -5SMuC, the middle one has a charge of +45 MuC, and the right one has a charge of -78 MuC. The middle particle is 72 cm from each of the others as shown below. a. Find the net force on the middle particle. b. Find the net force on the right particle.

Answer 1

Answer 2

a)

F=F₅₅+F₇₈

F=(9*10^9)(45*10^-6)[(-55/0.72²)+(-78/0.72²)]*10^-6

F=-103.91 N

b)

F=F₅₅+F₄₅

F=(9*10^9)(-78*10^-6)[45/0.72²-55/(0.72+0.72)²]*10^-6

F=-42.32 N

Answer 3

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Force of 45 = Force duw to -55    + force due to -78

F45 = (9e9 * -55e-6*45e-6/0.72^2) - (9e9 * 45e-6 *-78e-6/(0.72^2)

F45 = 42.96 - 60.937

F45 = -17.977 N

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F78 = F45 + RF55

F78 = (9e9 *-78e-6*45/0.72^2)-(9e9 *-78e-6*-55e-6/(1.44^2)

F78 = 42.32 N
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