How Do You Calculate Force Components and Moments in Vector Problems?

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To find the component of force F in the direction of displacement s, the angle between the two vectors is crucial, and it's often easiest to align the axes with one of the vectors for calculation. The moment of force F, when applied at position r, is calculated using the cross product, represented as r X F. This approach simplifies the process of determining the moment by focusing on the relationship between the displacement and the force. Understanding these vector operations is essential for solving related physics problems effectively. Proper application of these principles will lead to accurate calculations in vector problems.
greg997
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Hi,
I ve got two questions.

1. how to find the component of the force F in the direction of the displacement s?

I have two vectors and angle between them.


2. how to find moment of force F when applied at position r= 2a+7b-3c


No idea how to start:(. Thanks for helping me.
 
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1) It very much depends on the angle doesn't it? Then which axes you choose to determine he result. I usually choose the axes that make calculation the easiest - like along one of the vectors.

2) Moment is r X F. Your interest then will be in the cross product between the displacement and the force.
 
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