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A group of three separate point charges q1, q2, and q3 sits near a given point in space. According to the way electric potential from multiple charges is found, how is the total potential at that point calculated?
ABy multiplying the individual potentials k q1/r1, k q2/r2, and k q3/r3 together
BBy using only the potential from the single largest of the three charges
CBy adding the individual potentials k q1/r1, k q2/r2, and k q3/r3 as plain numbers
DBy adding the individual potentials as vectors, accounting for direction
Answer & Solution
Correct answer: C. By adding the individual potentials k q1/r1, k q2/r2, and k q3/r3 as plain numbers
1. Electric potential from a point charge is a plain number, not a vector with a direction.
2. The potential from several charges at one point is found by adding these plain numbers together.
3. Treating potential as a vector, as in option D, confuses it with the electric field, which does have direction.
4. Ignoring the smaller charges, as in option B, would throw away real contributions to the total potential.
_Source: OpenStax Physics (CC BY 4.0), Ch 18 "Static Electricity", section 18.4 Electric Potential_
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