A vector requires both magnitude and what other component?

A vector is defined as a quantity that has both magnitude and direction. The magnitude represents how much of the quantity there is, while the direction indicates where that quantity is pointing. In physics, this is important because many concepts, such as velocity, force, and displacement, are vector quantities.

For example, when discussing velocity, knowing just the speed (the magnitude part) is insufficient without also knowing the direction the object is moving. This combination allows for a complete description of the motion. In contrast, options like speed, distance, and position do not encompass the essential directional aspect required for a vector.

Speed, for instance, is a scalar quantity, which means it only has magnitude and does not include direction. Distance is also a scalar quantity representing how much ground an object has covered without regard to the direction. Position, while providing a point in space, does not indicate how that position relates directionally to the origin or other points in space without further context. Therefore, the correct answer highlights that direction is the crucial component that pairs with magnitude to fully define a vector.