Question

Demonstrate this result for the parallel calculation.

CODE:

from Tkinter import *
# MODIFY THIS TO HANDLE THREE RESISTORS

__author__ = "robincarr"

""" GUI version of Resistor Calculator finds the equivalent resistance for two resistors
connected either in series or parallel. Features entry widgets and buttons."""



def series_calculation():
    r1 = float(resistor1.get())
    r2 = float(resistor2.get())
    req = r1 + r2
    equivalent_resistance.delete(0, END)  # Clear the previous result.
    equivalent_resistance.insert(0, req)
    print("Resistor 1: %s\nResistor 2: %s" % (r1, r2))
    print "The equivalent series resistance is: ", req, "\n"


def parallel_calculation():
    r1 = float(resistor1.get())
    r2 = float(resistor2.get())
    req = r1 * r2 / (r1 + r2)
    equivalent_resistance.delete(0, END)  # Clear the previous result.
    equivalent_resistance.insert(0, req)
    print("Resistor 1: %s\nResistor 2: %s" % (r1, r2))
    print "The equivalent parallel resistance is: ", req, "\n"


root = Tk()
root.title("Resistor Calculator")

Label(root, text="Resistor 1").grid(row=0)
Label(root, text="Resistor 2").grid(row=1)
# 1. Add a label for the third resistor here in row 2.

resistor1 = Entry(root)  # Entry widget for Resistor 1.
resistor2 = Entry(root)  # Entry widget for Resistor 2.
# 2. Add an entry widget for Resistor 3 here.


resistor1.grid(row=0, column=1)  # Specify the location in the grid layout.
resistor2.grid(row=1, column=1)  # Specify the location in the grid layout.
# 3. Place resistor 3 here.

# 4 Now adjust the calculation callbacks to handle three resistors instead of 2.




# All that follows has already been shifted down one row for your convenience.

seriesButton = Button(root, text='Series', command=series_calculation)
seriesButton.grid(row=3, column=0, sticky=W, pady=4)


Button(root, text='Parallel', command=parallel_calculation).grid(row=3, column=1, sticky=W, pady=4) # Added
Button(root, text='QUIT', command=root.quit).grid(row=3, column=2, sticky=W, pady=4)  # Added


Label(root, text="Equivalent Resistance").grid(row=4) # Added

equivalent_resistance = Entry(root)
equivalent_resistance.grid(row=4, column=1) # Added

root.mainloop()

Answer 1

from Tkinter import *
# MODIFY THIS TO HANDLE THREE RESISTORS

__author__ = "robincarr"

""" GUI version of Resistor Calculator finds the equivalent resistance for two resistors
connected either in series or parallel. Features entry widgets and buttons."""

def series_calculation():
r1 = float(resistor1.get())
r2 = float(resistor2.get())
r3 = float(resistor3.get())
req = r1 + r2 + r3
equivalent_resistance.delete(0, END) # Clear the previous result.
equivalent_resistance.insert(0, req)
print("Resistor 1: %s\nResistor 2: %s\nResistor 3: %s" % (r1, r2, r3))
print "The equivalent series resistance is: ", req, "\n"

def parallel_calculation():
r1 = float(resistor1.get())
r2 = float(resistor2.get())
r3 = float(resistor3.get())
req = (r1 * r2 * r3 )/ (r1 * r2 + r2 * r3 + r3 * r1)
equivalent_resistance.delete(0, END) # Clear the previous result.
equivalent_resistance.insert(0, req)
print("Resistor 1: %s\nResistor 2: %s\nResistor 3: %s" % (r1, r2, r3))
print "The equivalent parallel resistance is: ", req, "\n"

root = Tk()
root.title("Resistor Calculator")

Label(root, text="Resistor 1").grid(row=0)
Label(root, text="Resistor 2").grid(row=1)
Label(root, text="Resistor 3").grid(row=2)
# 1. Add a label for the third resistor here in row 2.

resistor1 = Entry(root) # Entry widget for Resistor 1.
resistor2 = Entry(root) # Entry widget for Resistor 2.
resistor3 = Entry(root) # Entry widget for Resistor 3.
# 2. Add an entry widget for Resistor 3 here.

resistor1.grid(row=0, column=1) # Specify the location in the grid layout.
resistor2.grid(row=1, column=1) # Specify the location in the grid layout.
resistor3.grid(row=2, column=1) # Specify the location in the grid layout.
# 3. Place resistor 3 here.

# 4 Now adjust the calculation callbacks to handle three resistors instead of 2.

# All that follows has already been shifted down one row for your convenience.

seriesButton = Button(root, text='Series', command=series_calculation)
seriesButton.grid(row=3, column=0, sticky=W, pady=4)

Button(root, text='Parallel', command=parallel_calculation).grid(row=3, column=1, sticky=W, pady=4) # Added
Button(root, text='QUIT', command=root.quit).grid(row=3, column=2, sticky=W, pady=4) # Added

Label(root, text="Equivalent Resistance").grid(row=4) # Added

equivalent_resistance = Entry(root)
equivalent_resistance.grid(row=4, column=1) # Added

root.mainloop()