20.0-Forces in a Three-Charge System Coulomb\'s law for the magnitude of the for
ID: 1399604 • Letter: 2
Question
20.0-Forces in a Three-Charge System
Coulomb's law for the magnitude of the force Fbetween two particles with charges Q and Qseparated by a distance d is
|F|=K|QQ|d2,
where K=140, and 0=8.854×1012C2/(Nm2) is the permittivity of free space.
Consider two point charges located on the x axis: one charge, q1 = -14.5 nC , is located atx1 = -1.750 m ; the second charge,q2 = 39.0 nC , is at the origin (x=0.0000).
Part A
What is the net force exerted by these two charges on a third charge q3 = 45.5 nCplaced between q1 and q2 at x3 = -1.225 m ?
Your answer may be positive or negative, depending on the direction of the force.
Explanation / Answer
given,
q1 = -14.5 * 10^-9 C
q2 = 39 * 10^-9 C
q3 = 45.5 * 10^-9 C
q1 is located in x1 = -1.75 m
q2 is located in x2 = 0 m
q3 is located in x3 = -1.225 m
force between two charfed particles = k * Q * Q' / d^2
let force between q1 and q3 be f1
f1 = 9 * 10^9 * (-14.5 * 10^-9) * 45.5 * 10^-9 / (1.75 - 1.225)^2
f1 = -2.15 * 10^-5 N
let force between q2 and q3 be f2
f1 = 9 * 10^9 * 39 * 10^-9 * 45.5 * 10^-9 / 1.225^2
f1 = 1.064 * 10^-5 N
net force = f1 + f2
net force = -2.15 * 10^-5 + 1.064 * 10^-5
net force = -1.086 * 10^-5 N
et force exerted by these two charges on a third charge = -1.086 * 10^-5 N
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.