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Question
An electric current I flows through an infinitely long conductor as shown in Figure 2 (a) below. Write an expression and direction for the magnetic field at point P.
Solution
`therefore` By Biot savart’s law
`vec(B) = ∫ vec (dB) = mu_0/(4pi) ∫ (I vec(dl) xx vec(r))/r^3`
The magnetic field created by a current carrying wire is radial magnetic field.
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