National League for Nursing (NLN PAX) Practice Exam

A quantity that has both magnitude and direction is defined as a vector. Vectors are fundamental in physics and engineering because they represent quantities such as force, velocity, and displacement, where knowing the direction is as important as knowing the size (magnitude) of the quantity. For example, when describing the wind's speed and direction, it is essential to indicate not just how fast the wind is blowing (magnitude) but also in which direction it is blowing.

In contrast, scalar quantities possess only magnitude and do not include directional information. Common examples of scalars include temperature, mass, and speed. These do not require direction and are characterized solely by their size.

The terms gradient and field are associated with more complex concepts in physics and mathematics. A gradient describes the rate and direction of change in a scalar field, while a field refers to a physical quantity represented at each point in space, like an electric field or gravitational field. Neither of these options fits the definition of a quantity that combines both magnitude and direction as directly as a vector does.