CBSE-XI-Physics
35: Magnetic Field due to a Current
- #2The magnetic field due to a long straight wire has been derived in terms of µ, i and d. Express this in terms of ε0, c, i and d.Ans : The magnetic field due to a long, straight wire is given by
`` B=\frac{{\,\mathrm{\,\mu \,}}_{\,\mathrm{\,o\,}}i}{2\,\mathrm{\,\pi \,}d}``
`` \because \,\mathrm{\,Speed\,}\,\mathrm{\,of\,}\,\mathrm{\,light\,},\,\mathrm{\,c\,}=\frac{1}{\sqrt{{\,\mathrm{\,\mu \,}}_{\,\mathrm{\,o\,}}{\,\mathrm{\,\epsilon \,}}_{\,\mathrm{\,o\,}}}}``
`` \Rightarrow {\,\mathrm{\,\mu \,}}_{\,\mathrm{\,o\,}}=\frac{1}{{\,\mathrm{\,c\,}}^{2}{\,\mathrm{\,\epsilon \,}}_{\,\mathrm{\,o\,}}}``
`` \Rightarrow B=\frac{i}{2{\,\mathrm{\,\pi c\,}}^{2}{\,\mathrm{\,\epsilon \,}}_{\,\mathrm{\,o\,}}d}``
(In terms of ε0, c, i and d)
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