In the figure below, two charges (q13.00 C and q2 -9.0 C) are separated by a dis
ID: 2303728 • Letter: I
Question
In the figure below, two charges (q13.00 C and q2 -9.0 C) are separated by a distance L = 12 m and are held in place. Where would you place a third particle of unknown charge in order for the net electrostatic force on particle 3 from particles 1 and 2 to be zero? What is the type of charge (positive or negative)? Hint there are three possible regions for particle 3 to exist: to the left of 1, in the middle, and to the right of 2. Determine the electrostatics for each region and determine which region is the only possible one of particle 3 to be in. 6)Explanation / Answer
to the right of Q2
In that region the influence of electric field is strong due to the strong magnitude charge is closer to it as compared to Q1 and also Q1 is away from region right? side to Q2 hence we can't ecpect 0 electric field to the right side of Q2.
between the Q1& Q2
net electric field between these two charges will point always towards negatively charge particle. So this region can't be suitable to place an additional charge in order to get 0 force.
to the left of Q1
in this region the influence of Q1 can be balanced by Q2 as Q is far apart from this region.
Now let us consider distance 'd' to the left of Q1 where net electric field considered to be zero
Then,
kQ1/d^2= kQ2/(L+d)^2
3/9= ( d/(12+d))^2
d= 16.4 m. (Ans)
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Foce will always equal to zero irrespective of the magnitude of charge because at that point net electric field considered to be zero.
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