Understanding Vector Notation: Solving Homework Equations

AI Thread Summary
The notation r_{12} typically indicates the distance from point 1 to point 2. This is commonly seen in the context of vector equations, such as Coulomb's law, where forces between charges are represented. The discussion highlights the confusion surrounding this notation, particularly for those using related laws like Biot-Savart. Users express frustration over remembering the correct interpretation of the notation. Understanding this vector notation is crucial for accurately solving physics homework problems.
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Homework Statement



Does
r_{12}
mean distance from point 1 to point 2, or point 2 to point 1?

Homework Equations


The Attempt at a Solution

 
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Where you typically see this notation is the vector form of Coulomb's law where electric force exerted by a charge q1 on a second charge q2 is written F12
 
Cheers, I'm using in it Biot-Savat law so same thing really. I always forget it, it drives me nuts! Thanks again.
 

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