20 questions linked to/from Why do we use cross products in physics?
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Moment of force about a point definition [duplicate]

In defining the moment of a force about a point as "the tendency of one or more applied forces to rotate an object about an axis [going through a point, hence also about a point]", I see it logical to ...
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Why is the angular momentum defined as the cross product of linear momentum and the radius? [duplicate]

I first searched why is Torque defined as a cross product and a lot of people answered that it is defined as a cross product because angular momentum is defined that way and it is only logical that ...
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Why is the direction of cross products of two vectors perpendicular to the plane? [closed]

Why is the direction of cross products of two vectors perpendicular to the plane? How is that possible?
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Torque direction meaning

I apologize if this question is dumb, but I've looked all over for a straightforward answer, and either I can't find one or either the terms are too complex for me to understand. I have only a ...
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Definition of vector cross product

I hope I'm right in saying that the cross-product, $\vec{A}\times \vec{B}$ of two vectors is defined by a right hand rule (e.g. if $\vec{A}$ points along the forefinger and $\vec{B}$ along the second ...
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Why do we use the whole radius vector in the angular momentum, and not just the unit vector?

Why don't we only use the unit vector of the radius? I was thinking that, all we need to know is the component of the linear momentum, perpendicular to it, so why use the magnitude of the radius ...
211 views

Why the cross product of two vectors gives a vector in an orthogonal direction? [duplicate]

I understood the concept of cross product with an example of Torque. I understood the concept. But what confuses me is that how can cross product of two orthogonal vector in a plane give us the ...
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1 vote
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Why is the cross product used in electrodynamics [closed]

For example, $F = I \times B$. Why would the force be perpendicular to both the magnetic field and the current? Why would the resultant force be totally unlike its 2 sources; this could be likened to ...
584 views

What are the proper definitions of moment, couple, torque, 'moment of force'?

When I read some scientific articles I am getting confused with the interchange being used between Torque, Couple, Moment, 'Moment Of Force'. Have I got this correct? Moment is supposed to be some ...
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Definition of angular momentum about an axis and conservation of the angular momentum about the axis

I am reading this book Vector Mechanics for Engineers. On page 1332, I read about the Conservation of the angular momentum about the axis of precession and Conservation of the angular momentum about ...
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