13) and (4 14),
(
)
π
0
3/2
2
2
d
d
4
x
I l
R
B
x
R
=µ
+
The summation of elements dl over the loop yields 2pR, the
circumference of the loop Thus, the magnetic field at P due to entire
circular loop is
(
)
2
0
3/2
2
2
ˆ
ˆ
2
x
I R
B
x
R
µ
=
=
+
B
i
i
(4 15)
As a special case of the above result, we may obtain the field at the centre
of the loop