Weight of Steel bar

 # Weight of Steel bar

"""

unit weight of steel bars is D²/162 kg/m. D is the Diameter Of steel bars, 162 is a constant value. 

"""

D = eval(input("Enter diameter of steel bar (in meter) : "))

wt = D*D/162

print("Weight of steel bar = ",round(wt,2),"kg/m")

"""

Sample output

>python wtofsteelbar.py

Enter diameter of steel bar (in meter) : 20

Weight of steel bar =  2.47 kg/m

"""