As Shown In Figure Conductor Carrying Current I

As shown in figure a conductor carrying a current I. Find the magnetic field intensity at the point ”O”. (a) (5/ … (d) -…

Answers:

The correct option (d) – (5/24)(μ0/π)(1/r)θ k

Explanation:

 Here B3 = B5 = B7 = 0

B2 = (μ0/4π)[I/(r + r + r)]θ = (μ0/4π)(I/3r)θ going inside

B4 = (μ0/4π)[I/(r + r)]θ = (μ0/4π)(I/2r)θ  coming outside

B6 = (μ0 / 4π)(I/r)θ   going inside

∴ Total magnetic field = B2 + B4 – B6

 ∴ B = – (μ0/4π)(I/3r)θ – (μ0/4π)(I/r)θ + (μ0/4π)(I/2r)θ

 = (μ0/4π)θI [– (1/3r) – (1/r) + (1/2r)]

= [(μ0θI)/4π] [(– 2 – 6 + 3)/(6r)]

= [(– 5)/24π] μ0θI (1/r)k