Here we plot the height of the ball during the first second of its movement:

%matplotlib inline
%config InlineBackend.figure_format = 'retina'
import matplotlib.pyplot as plt
import numpy as np

def plot_ball():
    t = np.linspace(0,1)
    plt.figure(figsize=(4,2))
    plt.plot(t, ball_height(t))
    plt.xlabel('time (sec)')   
    plt.ylabel('height (meters)') 
    plt.title('Ball height vs time', fontsize=10)
    plt.show()

def ball_height(t, v_0=10):
    g = 9.81
    return v_0*t - 0.5*g*t**2

plot_ball()