To calculate the velocity of the horse, we can use the formula for average velocity:
\[ \text{Velocity} = \frac{\text{Total Displacement}}{\text{Total Time}} \]
In this case, the horse travels around a track and ends up back at the starting point. This means the total displacement is 0 meters. The total time taken is 40 seconds.
Now we can plug in the values:
\[ \text{Velocity} = \frac{0 , \text{m}}{40 , \text{s}} = 0 , \text{m/s} \]
So, the horse's velocity is 0 m/s.