A tennis ball of mass 0.058 kg moves at 50 m s⁻¹.

Step 1. Wavelength. $\lambda = \dfrac{6.626 \times 10^{-34}}{0.058 \times 50} = 2.3 \times 10^{-34}\ \text{m}$.

Step 2. Compare. $\dfrac{10^{-15}}{2.3 \times 10^{-34}} \approx 4 \times 10^{18}$: the wavelength is that many times smaller than a nucleus.

Step 3. Meaning. No experiment could ever show waves this short, so a ball behaves as a plain particle.