A position vector expresses the position of an object from the origin of a coordinate system.
Position vector is basically a straight line which has one of its ends end fixed to a body and whereas, the other end is attached to a moving point which tells the position of that specific point relative to the body. As the point accelerates, the position vector will vary its length and the direction accordingly.
Sample Response: Pick a reference point on the line to be the zero position. Determine the direction and measure the distance from zero in standard units.