#!/usr/bin/env python
# coding: utf-8

# In[11]:


m=1 # [kg] mass of the object
x=5;# initial position
v=0 # initial velocity
g=9.814 #[m/s^2] gravitational constant Lisbon
F=-m*g
dt=0.003 # [s] time advance
t=0 # [s] initial time


# In[12]:


Time = []
Position=[]
while x>0:  
  t=t+dt # time evolution
  Time.append(t)
  a=F/m # acceleration "evolution"
  v=v+a*dt # velocity evolution
  x=x+v*dt # position evolution
  Position.append(x)


# In[13]:


from matplotlib import pyplot
pyplot.plot(Time, Position)
pyplot.xlabel('t [s]');pyplot.ylabel('x [m]');