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 ...
984 views

### 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? 9k views

### 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 ...
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### 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 ...
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 ...
313 views

### 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 ...
1 vote