Units of Coulomb, trouble understanding the question

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    Coulomb Units
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The discussion centers on calculating the force between two charges, q1 = 4.9 e C and q2 = -3.6 e C, which are 105 nm apart, using the formula F = kqq/r^2. The initial confusion arose from the interpretation of "e C," leading to uncertainty about whether to multiply by the elementary charge value of 1.6 x 10^-19 C. It was clarified that "e" already represents this value, meaning q1 should not be treated as having a unit of Coulomb-Coulomb. Ultimately, the misunderstanding was resolved, confirming that the values for q1 and q2 are correctly expressed in terms of elementary charge. The problem was deemed solved.
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Homework Statement


Two charges, q1 = 4.9 e C and q2 = -3.6 e C are located 105nm apart, what is the size of the force between the two charges?

Homework Equations



F=kqq/r^2

The Attempt at a Solution



I did it according to the formula and I got the answer wrong, so I checked it using an online force calculator between charges, and it gave the same answer I initially got. I looked up what e C is, thinking maybe it's indicating something smaller than 1 C, and couldn't really find a graduation for that, what am I doing wrong? Is it meant to be multiplied by 1.6 x 10^-19?
 
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Actually q_1 = 4.9 e C is somewhat incorrect. e = 1.6\times10^{-19}C is the elementary charge and already contain the unit Coulomb. So it is as if q_1 has unit Coulomb-Coulomb.
 
mathfeel said:
Actually q_1 = 4.9 e C is somewhat incorrect. e = 1.6\times10^{-19}C is the elementary charge and already contain the unit Coulomb. So it is as if q_1 has unit Coulomb-Coulomb.

So does this mean that I have to multiply 4.9 by 1.6x10^-19?
 
Nvm, problem(s) solved.
 
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