The sign convention here is that a positive at represents a vector that is tangent to the circle and points in the direction of increasing θ (that is, counterclockwise); the full acceler...The sign convention here is that a positive at represents a vector that is tangent to the circle and points in the direction of increasing θ (that is, counterclockwise); the full acceleration vector is equal to the sum of this vector and the centripetal acceleration vector, introduced in the previous subsection, which always points towards the center of the circle and has magnitude
