Q. 24.7( 3 Votes )
The magnetic field due to a long straight wire has been derived in terms of μ0, i and d. Express this in terms of ϵ0, c, i, and d.
Magnetic field at a point d distance apart from a long straight current carrying wire is given by from Ampere’s circuital law. Where μ0 is the magnetic permeability of free space, i denotes the current through the wire and d denotes the distance from the wire, of the point where magnetic field is to be calculated.
Now we know that, speed of light, (ϵ0 denotes the electric permittivity of free space)
c2 = μ0 ϵ0
Thus we get magnetic field to be
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