Question

is a vector necessarily changed if it is rotated through an angle

Answer 1

If the angle of a vector is changed, then most likely the vector ischanged. A vector will not change if it is rotated through 360o, or a multiple of 360o as long as its magnitude remains the same.

Answer 2

Vector actually denotes the angle of propagation.



So when an object moves around a circular path, the direction continuously changes.


Therefore the vector quantity must also chang frequently along d circular orbit
.