#orange ball rolling across a green lawn
#ball slows down in this variation  python 11
import random
import time
from Tkinter import *
frmMain = Tk()
myCanvas = Canvas(width=400, height=400, background="sky blue")
myCanvas.create_rectangle(0,300,400,400,fill="dark green")
oldx = 0
sleeptime = 0.1      #we'll slow this down
while oldx < 350:
    myCanvas.create_oval(oldx,275,oldx+25,300,fill="orange",\
                         outline="orange")
    myCanvas.pack()
    myCanvas.update()
    time.sleep(sleeptime)
    myCanvas.create_oval(oldx,275,oldx+25,300,fill="sky blue",\
                         outline="sky blue")
    oldx = oldx + 5
    sleeptime = sleeptime + 0.005

myCanvas.pack()
frmMain.mainloop()