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The constant k, which appears in the equation for Coulomb’s law, is equivalent dimensionally to which of the following?

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Correct Answer: D. N?m2/C2
The SI unit for force F is newtons N and for q, the SI unit is coulombs C and, of course, meters m is the SI unit for length/distance symbolized as r in Coulomb’s law.
Using Coulomb’s equation: F = kq1q2/r2
We get in SI units: N = k (C)(C)/m2 = k (C)2/m2
And so isolating for k: k = N?m2/C2
Expect questions requiring dimensional analysis on the real exam.
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