Linked Questions
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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Why is torque defined as $\vec{r} \times F$?
Here I cannot convince myself myself that it is units because the torque is defined to be in units of Newton meter is a reiteration of the law stated above. Why was it not $r^2 \times F$ or $r^3 \...
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In Circular motion, why $v = \omega × r$?
When I was at high school they teached me this formula $v = \omega × r$, it is the formula for knowing the linear velocity out of an angular velocity. But I've never understand why this works, even ...
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Can someone provide an intuitive relation between linear and angular velocity?
I know the written derivation of $v=rω$, we just differentiate $∆s$ and $r∆\theta$ but can someone please provide an intuitive derivation.
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Why is the $B$-Field an axial Vector? [duplicate]
in trying to understand the Wu-Experiment I wonder why the $B$-Field is an axial vector. I know that $\vec{B} = \vec{\nabla} \times \vec{A}$. Under Parity transformation I'd expect $\vec{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 ...
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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 ...
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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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Law of the lever - Explained Physically
Thanks for reading.
I've seen the "Archimedes Proof" of the law of the lever, and many similar ones, but...at the end of the day, all they're doing is getting observations about the way ...