A 100-meter sprint is a race using only the straight side of a racetrack. A 400-meter sprint is a race that makes one complete lap around a racetrack. Why are velocity and speed the same for a 100-m sprint but not a 400-m sprint?

Answer:

In the 100m sprint, the displacement is 100 meters and the distance is 100 meters. This means speed and velocity are the same for the 100m sprint. In the 400m sprint, the distance is 400m, but the runners stop at the same place they start so the displacement is zero. Zero displacement means zero velocity.