What does the in equations stand for?

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The dot in equations, such as in the expression ΔE_{p} = k . Q_{1} Q_{2} [ \frac{1}{r_{1}} - \frac{1}{r_{2}}], represents multiplication. This notation is used to prevent confusion with the variable symbol "×," which can also denote a variable in mathematical contexts. The dot is specifically a midline dot, distinct from a period. This method of denoting multiplication is common in physics and mathematics to enhance clarity. Understanding this notation is essential for correctly interpreting equations involving multiple variables.
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What does the "." in equations stand for?

I've been revising electric fields, and have come across the equation \Delta E_{p} = k . Q_{1} Q_{2} [ \frac{1}{r_{1}} - \frac{1}{r_{2}}]

I have never come across a decimal point in an equation before, what does it mean?
 
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"." is another way of saying "multiplied by"
 
It is to avoid using \times which can be used to represent a variable. It would cause confusion hence a dot is used to show multiplication.
 
Note, it's not a period, as in [ilatex]a . b[/ilatex], it's a midline-dot, like [ilatex]a \cdot b[/ilatex]

- Warren
 
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