Which of the following quantities is always a vector?

Which of the following quantities is always a vector?

• A. Speed
• B. Acceleration
• C. Distance
• D. Time

Answer: (B)

The correct choice is acceleration because it is defined as the rate of change of velocity with respect to time. As a vector quantity, acceleration has both a magnitude and a direction. The direction of acceleration indicates how the velocity of an object is changing; for example, if an object is speeding up, the acceleration is in the same direction as its velocity, whereas if it is slowing down, the acceleration is in the opposite direction. In contrast, speed is a scalar quantity that only has magnitude and does not include direction. Distance is also a scalar measure that represents the total path length traveled, regardless of direction. Time is a scalar quantity as well, indicating duration without any directional component. Therefore, the unique characteristic of acceleration as a vector quantity distinguishes it from speed, distance, and time.

The correct choice is acceleration because it is defined as the rate of change of velocity with respect to time. As a vector quantity, acceleration has both a magnitude and a direction. The direction of acceleration indicates how the velocity of an object is changing; for example, if an object is speeding up, the acceleration is in the same direction as its velocity, whereas if it is slowing down, the acceleration is in the opposite direction.

In contrast, speed is a scalar quantity that only has magnitude and does not include direction. Distance is also a scalar measure that represents the total path length traveled, regardless of direction. Time is a scalar quantity as well, indicating duration without any directional component. Therefore, the unique characteristic of acceleration as a vector quantity distinguishes it from speed, distance, and time.