Question

In the figure particle 1 of charge q1-0.98 μC and particle 2 of charge q2--237 μC, are held at separation L-10.9 cm on an x axis. If particle 3 of unknown charge q3 is to be located such that the net electrostatic force on it from particles 1 and 2 is zero, what must be the (a)x and (b)y coordinates of particle 3? (a) Number Units (b) Number Units

Answer 1

a)

let us consider "d" is the distance left to point 1

now, in order to get net electric force at that point to be zero, magnitude of both the electric field must be equal so that they cancel out each other hence we must equalise electric field due to charge 1 and charge 2 at that point,

so,

k q1 / d^2 = k q2 / (L+d) ^2

q2/q1 = [ (L +d) / d ] ^2

2.97 / 0.98 = [ 10.9 / d +1 ] ^2

d = 14.71 cm

x coordinate of this point = - 14.71 cm ( Ans)

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b) since all the calculations are carrying out in x axis, so y co ordinate must be 0

y = 0 ( Ans)

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