Resistance of tungsten wire at $150\,^oC$ is $133\,\Omega $. Its resistance temperature coefficient is $0.0045\,^oC$. The resistance of this wire at $500\,^oC$ will be .............. $\Omega$
A$180$
B$225$
C$258$
D$317$
Medium
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C$258$
c (c) $\frac{{{R_{150}}}}{{{R_{500}}}} = \frac{{[1 + \alpha (150)]}}{{[1 + \alpha (500)]}}$. Putting ${R_{150}} = 133\,\Omega $ and $\alpha = 0.0045\,^o C,$ we get ${R_{500}} = 258\,\Omega $
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