Question concerning the direction of the vector r in the FL

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The discussion focuses on the direction of the vector r in the Feynman Lectures of Physics, specifically in Chapter 13.3. The original question seeks clarification on whether vector r in equation 13.5 points from mass mj to mass mi. Participants confirm that the convention illustrated in figure 13.2 indicates vectors point from 1 to 2, and there is a suggestion that the vector should be consistent across equations 13.15 and 13.16. Overall, the consensus is that the vector direction should align with the established conventions in the text.
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Hello! I've got a question concerning the direction of the vector r in the Feynman Lectures of Physics in Chapter 13.3 http://www.feynmanlectures.caltech.edu/I_13.html#Ch13-S3

Which direction does the vector r in equation 13.5 point in?
The long equation before equation 13.6 suggests that it should point from ##m_{j}## to ##m_{i}##.

Is that correct?
 
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The convention is given in figure 13.2: the vectors point from 1 to 2.
 
Do you mean 13.15 and 13.16?
 
dauto said:
Do you mean 13.15 and 13.16?
The vector should be the same in both equations.
 
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