A wire of length 1.0 m and radius 10^(-3) m is carrying a heavy current and is assumed to radiate as a black body. At equilibrium, its temperature is 900K, while that of the surroundings is 300K. The resistivity of the material of the wire at 300K is pi^(2)xx10^(-8) ohm-m and its temperature coefficient of resistance is 7.8xx10^(-3)//""^(0)C. The current (in ampere) in the wire is 6x. Find .x.. (Given Stefan.s constant =5.68xx10^(-8)" W"//"m"(2)//K^(-4)).

A wire of length 1.0 m and radius 10^(-3) m is carrying a heavy curren

1.	A wire of length 1.0 m and radius 10^(-3) m is carrying a heavy current and is assumed to radiate as a black body. At equilibrium, its temperature is 900K, while that of the surroundings is 300K. The resistivity of the material of the wire at 300K is pi^(2)xx10^(-8) ohm-m and its temperature coefficient of resistance is 7.8xx10^(-3)//""^(0)C. The current (in ampere) in the wire is 6x. Find .x.. (Given Stefan.s constant =5.68xx10^(-8)" W"//"m"(2)//K^(-4)).
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