is this correct only for " the tangential unit vector " ?
because according to what I learned , any vector can be in the opposite direction of its unit vector and specified by a negative sign.
however , in case of " the tangential unit vector " , as I understood from you ; the unit vector...
[SIZE="4"]we already know that the scalar component of the Centripetal ( Radial ) Acceleration vector is always negative because it's ALWAYS directed to the opposite direction of its unit vector ( toward the center of the circle ) , and this is satisfying to me and to the formula .
however ...