3.227. A very long wire carrying a current I = 5.0 A is bent
at right angles. Find the magnetic induction at a point lying on a per-
pendicular to the wire, drawn through the point of bending, at
a distance 1 = 35 cm from it.
3.228. Find the magnetic induction at the point 0 if the wire car-
rying a current I = 8.0 A has the shape shown in Fig. 3.63 a, b, c.Fig. 3.63.The radius of the curved part of the wire is R = 100 mm, the linear
parts of the wire are very long.
3.229. Find the magnitude and direction of the magnetic induction
vector B
(a) of an infinite plane carrying a current of linear density i;
the vector i is the same at all points of the plane;
(b) of two parallel infinite planes carrying currents of linear den-
sities i and —i; the vectors i and —i are constant at all points of
the corresponding planes.
3.230. A uniform current of density j flows inside an infinite
plate of thickness 2d parallel to its surface. Find the magnetic induc-
tion induced by this current as a function of
the distance x from the median plane of the
plate. The magnetic permeability is assumed
to be equal to unity both inside and outside
the plate.
3.231. A direct current I flows along a
lengthy straight wire. From the point 0(Fig. 3.64) the current spreads radially all (^0)
over an infinite conducting plane perpendicu-
lar to the wire. Find the magnetic induction Fig. 3.64.
at all points of space.
3.232. A current I flows along a round loop. Find the integral
B dr along the axis of the loop within the range from —00 to +00.
Explain the result obtained.
3.233. A direct current of density j flows along a round uniform
straight wire with cross-section radius R. Find the magnetic induction
vector of this current at the point whose position relative to the axis
of the wire is defined by a radius vector r. The magnetic permeability
is assumed to be equal to unity throughout all the space.
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