A long straight wire of resistance $R$, radius $a $ and length $ l$ carries a constant current $ I.$ The Poynting vector for the wire will be

  • A

    $\frac{{IR}}{{2\pi al}}$

  • B

    $\frac{{I{R^2}}}{{al}}$

  • C

    $\frac{{{I^2}R}}{{al}}$

  • D

    $\frac{{{I^2}R}}{{2\pi al}}$

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