Which of the following quantities is a vector?

• A. $\text{Speed}$
• B. $\text{Mass}$
• C. $\text{Distance}$
• D. $\text{Displacement}$

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the difference between scalar and vector quantities. Scalars have only magnitude (size), while vectors have both magnitude and direction.
2. Step 2: Analyze each quantity given: Speed is a scalar because it only tells how fast an object is moving, without direction.
3. Step 3: Mass is a scalar because it represents the amount of matter in an object and has no direction.
4. Step 4: Distance is a scalar because it measures the total length of the path traveled, regardless of direction.
5. Step 5: Displacement is a vector because it represents the shortest straight-line distance from the starting point to the ending point, including direction.