Comparing ωxr and rxω in Vector Calculations

AI Thread Summary
The discussion focuses on the use of ωxr versus rxω in vector calculations, highlighting that the order of the cross product significantly affects the direction of the resultant vector. While the magnitudes remain the same, the direction will be opposite depending on the order used. Context is crucial, as specific physical laws dictate which order to use to ensure the correct direction in a right-handed coordinate system. Understanding the problem's requirements is essential for determining the appropriate cross product. The conversation emphasizes the importance of convention and context in vector calculations.
Icetray
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Hi guys,

I just wanted to know when to use ωxr and when to use rxω when we're making vector based calculations. I realized that when reversed te calculations tend to differ a lot.

Thanks for the help in advance!
 
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AxB = -BxA

It's strictly convention. The magnitude of the vector you get will be the same either way, however, it will be in the opposite direction. You need to think about the problem asked to figure out which way you should perform the cross product.
 
Icetray said:
Hi guys,

I just wanted to know when to use ωxr and when to use rxω when we're making vector based calculations. I realized that when reversed te calculations tend to differ a lot.

Thanks for the help in advance!

They result in a different direction for the resultant (diametrically opposite direction, actually). The cross product is a mathematical operation that is order dependent.

There is no way to answer your question without knowing the context; If a physical "law" is involved then the order is specified to result in the correct direction given that the vectors involved are specified in a standard "right handed" coordinate system.
 
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