Final answer:
The statement is false; a scalar does not become a vector simply by adding an arrowhead since a vector needs to have both magnitude and direction.
Step-by-step explanation:
The statement that a scalar quantity becomes a vector quantity if the direction of a line is represented by an arrowhead is false. A scalar is a physical quantity that has magnitude only, but no direction. In contrast, a vector has both magnitude and direction. To represent a vector, one may use arrows, where the magnitude is indicated by the length of the arrow and the direction is indicated by the arrowhead. When we are drawing vectors, the direction is an essential component, and it's often shown as an angle from a reference direction, such as from the horizontal or using compass points.