Question

a runner completes one lap around a circular track. explain how their speed and velocity differ during this motion.

Explanation:

Speed is a scalar quantity, the total distance (circumference of the track) divided by time taken. Velocity is a vector quantity. Since the runner returns to the starting - point, the displacement is zero. So average velocity over the whole lap is zero while speed is non - zero.

Answer:

Speed is non - zero as it's distance over time (the runner covers the length of the circular track). Velocity is zero for the whole lap because displacement (final position minus initial position) is zero as the runner ends at the starting point.