In a diagram of electric field lines,q₁ has 9 lines going into it and q₂ has 27 lines going out of it.If one of the charges is -40 mC,which of the following could be the other one? A) -120 mC B) 18.0 mC C) -18.0 mC D) 120 mC E) none of the these choices are correct

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Quizplus · Accepted Answer

According to Gauss's law, the total number of electric field lines passing through a closed surface is proportional to the charge enclosed by the surface. Therefore, we can assume that the two charges must produce a net charge of -18 mC because there are 18 more lines going out than coming in. One possible combination of charges that produces a net charge of -18 mC is -40 mC and 22 mC (since 27 - 9 = 18). Therefore, the only choice that is within this range is D, which has a charge of 120 mC and when paired with -40 mC, produces a net charge of -18 mC.

In a Diagram of Electric Field Lines,q1 Has 9 Lines

In a Diagram of Electric Field Lines,q₁ Has 9 Lines