import tkinter as tk
import math
def calcola():
      a=float(v1.get())
      b=float(r1.get())
      c=float(c1.get())
      d=float(t1.get())
      i=2
      valore=1
      while i>valore:
          i=(a/b)*math.e**(-d/(b*c))
          d=d+1
          print(i)


finestra1=tk.Tk()
finestra1.geometry('800x290')
finestra1.title('Scarica di un condensatore')
finestra1.configure(bg="orange")
v=tk.Label(finestra1, padx=20, pady=5, fg="blue", text="inserisci la differenza di potenziale", bg="orange",font=('helvetica',15,'bold'))
v.grid(column=0,row=0)
v1=tk.Entry(finestra1,width=25,justify="right",font=15)
v1.grid(column=1,row=0)
r=tk.Label(finestra1, padx=20, pady=5, fg="blue", text="inserisci la resistenza", bg="orange",font=('helvetica',15,'bold'))
r.grid(column=0,row=1)
r1=tk.Entry(finestra1,width=25,justify="right",font=15)
r1.grid(column=1,row=1)
c=tk.Label(finestra1, padx=20, pady=5, fg="blue", text="inserisci la carica", bg="orange",font=('helvetica',15,'bold'))
c.grid(column=0,row=2)
c1=tk.Entry(finestra1,width=25,justify="right",font=15)
c1.grid(column=1,row=2)
t=tk.Label(finestra1, padx=20, pady=5, fg="blue", text="inserisci il tempo", bg="orange",font=('helvetica',15,'bold'))
t.grid(column=0,row=3)
t1=tk.Entry(finestra1,width=25,justify="right",font=15)
t1.grid(column=1,row=3)
calcola=tk.Button(finestra1,width=25,text="calcola",font=45, bg="red", fg="yellow", command=calcola)
calcola.grid(column=1,row=4)
finestra1.mainloop()