To find the force that the floor exerts on the ball, we can use Newton's second law, which states that force is equal to mass times acceleration (F = m * a).
Here, the mass of the tennis ball (m) is 0.1 kg and the acceleration (a) is given as 10 m/s².
Now, we can calculate the force:
\[ F = m \cdot a \]
\[ F = 0.1 , \text{kg} \cdot 10 , \text{m/s}^2 \]
\[ F = 1 , \text{N} \]
Therefore, the force that the floor on the south end of the court exerted on the ball is 1 N.