Answer:
Because the person is changing direction
Explanation:
The acceleration of an object is defined as the rate of change of velocity:
[tex]a=\frac{\Delta v}{\Delta t}[/tex]
where
[tex]\Delta v[/tex] is the change in velocity
[tex]\Delta t[/tex] is the change in time
We must keep in mind that velocity is a vector, consisting of a speed and a direction. Therefore, a change in velocity means:
- either a change in the speed of the object, or
- a change in its direction
In this problem, the person is running around the track with a constant speed. However, his velocity is constantly changing (because the track is circular), this means that the change in velocity is not zero, and so there is a non-zero acceleration.
