Speed and Velocity

This lesson covers speed, velocity, and the equations of motion as required by the AQA GCSE Physics specification (4.5.6). Speed tells us how fast an object is moving, while velocity tells us both how fast and in which direction. These concepts are fundamental to understanding all aspects of motion and forces.

---

Speed

Speed is a scalar quantity that tells you how fast an object is moving. It is defined as the distance travelled per unit time.

The equation for speed is:

s = d / t

Where:

• s = speed (m/s)
• d = distance (m)
• t = time (s)

This equation can be rearranged:

• To find distance: d = s x t
• To find time: t = d / s

Exam Tip: The speed equation s = d / t is NOT on the AQA equation sheet — you must memorise it. Use the formula triangle: put d on top, and s and t on the bottom. Cover the quantity you want to find.

---

Typical Speeds

You must know typical speeds for different objects and situations. These are approximate values.