Calculate v - w*r: Vector, Cross Product

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The discussion revolves around calculating relative velocity using the equation v1 = v + wr - (v' + w'r'). Participants explore the implications of angular velocity and its representation in two dimensions, specifically addressing the components vx and vy. The cross product is highlighted as a potential method for calculating the relationship between vectors, with a suggestion that v can be expressed as v = w * r.perpendicular(). The conversation references a Wikipedia article on angular velocity for further clarification. Overall, the focus is on understanding the mathematical relationships between these vector quantities.
Isawyou0
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Hi!
seems crazy! but what if there is vx and vy?r is it a vector?
w*r can be a cross product?
 
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It would help if you defined your symbols.
 
Isawyou0 said:
Hi!
seems crazy! but what if there is vx and vy?r is it a vector?
w*r can be a cross product?

This wikipedia article should help: https://en.wikipedia.org/wiki/Angular_velocity

(see the part about particle motion in 3 dimensions...) :smile:
 
yes, yes, means that v=wr gives v in one dimension, right!
I want to calculate relative velocity, v1 = v + wr - ( v' + w'r' ) ; since that v is in 2d(v for x and y in euclidean space, as a vector velocity);
 
Isawyou0 said:
yes, yes, means that v=wr gives v in one dimension, right!
I want to calculate relative velocity, v1 = v + wr - ( v' + w'r' ) ; since that v is in 2d(v for x and y in euclidean space, as a vector velocity);

But the wikipedia page also shows the vector equation:

which, by the definition of the cross product, can be written:

115d67943a5d57b75784387fe225ccee.png
 
isn't it like:
v=w*r.perpendicular();
 
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