Define a vector quantity.

• A. A quantity that has both magnitude and direction
• B. A quantity with only magnitude
• C. A quantity with no direction
• D. A unit of measurement

Answer: (A)

A vector quantity has both magnitude and direction. This means it tells you how much of something there is and which way it points, so its value depends on both size and orientation. Examples include displacement (how far and in what direction you travel), velocity (speed with a direction), force (how strong and in which direction something pushes), and acceleration (how quickly velocity changes and in what direction). Quantities like mass, temperature, and time have only magnitude and no direction, so they are scalars. A unit of measurement describes the scale of magnitude but isn’t itself a quantity with direction, so it isn’t a vector.