(4 4),
Fba = Ib L Ba
      
0
2
a
I Ib
L
d
=µ
π
(4 23)
It is of course possible to compute the force on ‘a’ due to ‘b’ From
considerations similar to above we can find the force Fab, on a segment of
length L of ‘a’ due to the current in ‘b’