Velocity specifies direction along with magnitude, whereas speed is scalar.
Explanation
In kinematics, physical quantities are categorized as scalars or vectors based on their dependence on direction. While both speed and velocity measure the rate of motion, they differ fundamentally in their treatment of direction and the path traveled.- Velocity is a scalar quantity, while speed is a vector. is Incorrect: The classification is the reverse. Speed is a scalar quantity as it possesses only magnitude (how fast an object is moving). Velocity is a vector quantity as it possesses both magnitude and a specific direction.
- Velocity specifies direction along with magnitude, whereas speed is scalar. is Correct: The defining difference is that velocity specifies the direction of motion along with the magnitude. Speed refers only to the magnitude of the rate of change of position (distance/time), whereas velocity refers to the rate of change of displacement (displacement/time).
- Speed can be zero, but velocity is always non-zero for moving objects. is Incorrect: For a moving object that returns to its initial position, the net displacement is zero. Consequently, its average velocity is zero. However, since the total distance covered is positive, the average speed is non-zero. Thus, velocity can be zero for a moving object, but speed cannot.
- Velocity is always numerically greater than speed. is Incorrect: Speed is based on distance, while velocity is based on displacement. Since the distance traveled is always greater than or equal to the magnitude of displacement (shortest path), speed is always greater than or equal to the magnitude of velocity. Velocity cannot be numerically greater than speed.
Key Takeaway: Speed is a scalar quantity derived from distance, whereas Velocity is a vector quantity derived from displacement, necessitating both magnitude and direction.