Components of vectors (polar coordinates)

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A vector is not fixed in space, meaning it can be moved without altering its components in a Cartesian coordinate system. However, in polar coordinates, the components of a vector change when the vector is moved because the unit vectors vary with position. This is due to the curvilinear nature of polar coordinates, unlike Cartesian coordinates where unit vectors remain constant. Therefore, while a vector's length and direction remain unchanged, its representation in polar coordinates is dependent on its position. Understanding this distinction is crucial for working with vectors in different coordinate systems.
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I have always been under the impression that a vector is not "fixed" in space. Given any vector, we could just move it around and it would still have the same components (in a cartesian coordinate system). What confuses me, however, is how we define the components of a vector in polar coordinates. If we "move the vector around", we don't seem to get the same components (in polar coordinates). Does that mean that when talking about vectors in a polar coordinate system, we are not allowed to "move" the vector around?
 
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MohammedRady97 said:
I have always been under the impression that a vector is not "fixed" in space. Given any vector, we could just move it around and it would still have the same components (in a cartesian coordinate system)
The vector itself, as expressed in terms of the sum its components times the coordinate system unit vectors will not change, but, if the coordinate system is curvilinear (so that the directions of its unit vectors vary with spatial position), then the components expressed with respect to these unit vectors will change. Cartesian coordinates are not curvilinear, so its unit vectors are pointing in the same directions at each spatial position, and the components of a vector expressed with respect to this coordinate system do not change.

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