One of the first conceptual challenges IB Physics students face is distinguishing between speed and velocity. Although the two words seem similar in everyday language, they mean very different things in physics. Understanding this distinction is essential because it influences how you interpret motion graphs, calculate acceleration, and analyze forces. Students aiming for clear, confident explanations—especially those targeting a 7—benefit from mastering this idea early. This foundational clarity is emphasized throughout resources like The Quest for a 7 in IB Physics (https://www.revisiondojo.com/blog/the-quest-for-a-7-in-ib-physics) , where strong conceptual understanding is highlighted as a key to top performance.
Speed: A Scalar Quantity
Speed is defined as the distance traveled per unit time. Its formula is:
speed = distance / time
Speed is a scalar quantity, meaning it has:
- Magnitude only
- No direction
Examples of speed include:
- A car traveling at 60 km/h
- A runner moving at 5 m/s
- A plane cruising at 800 km/h
Because speed does not include direction, it cannot be negative. It also does not tell you anything about where the object is headed—only how fast it is moving. This difference becomes important when solving motion problems, especially in Paper 1. To become more efficient with these definitions, many students rely on the strategies found in How to Get a 7 in IB Physics (New Syllabus 2025 Onward) (https://www.revisiondojo.com/blog/how-to-get-a-7-in-ib-physics-new-syllabus-2025-onward) .
Velocity: A Vector Quantity
Velocity is defined as .
