At what temperature(in kelvin) would the resistance of a copper wire be half its resistance at `0^@C`? Temperature coefficient of resistance of copper is `3.9 xx 10^(-3).^(@)C^(-1)`.

At what temperature(in kelvin) would the resistance of a copper wire b

1.	At what temperature(in kelvin) would the resistance of a copper wire be half its resistance at `0^@C`? Temperature coefficient of resistance of copper is `3.9 xx 10^(-3).^(@)C^(-1)`.
Answer» Let at temperature `t^@C,R_(t)=1/2R_(0)` Then `alpha=(R_(t) -R_(0))/(R_(0)xxt)=((R_(0)//2)-R_(0))/(R_()xxt) = -(1)/(2t)` or `t = -(1)/(2 alpha) = - 1/( 2xx 3.9xx10^(-3))= -128.2^@C` `=144.8K`

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At what temperature(in kelvin) would the resistance of a copper wire be half its resistance at `0^@C`? Temperature coefficient of resistance of copper is `3.9 xx 10^(-3).^(@)C^(-1)`.

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