The maximum energy in the thermal radiation from a hot source occurs at a wavelength of $11 \times {10^{ - 5}}cm$. According to Wein's law, the temperature of the source (on Kelvin scale) will be $n$ times the temperature of another source (on Kelvin scale) for which the wavelength at maximum energy is $5.5 \times {10^{ - 5}}cm$. The value $n$ is
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(c)$\frac{{{T_1}}}{{{T_2}}} = \frac{{{\lambda _{{m_2}}}}}{{{\lambda _{{m_1}}}}} = \frac{{5.5 \times {{10}^5}}}{{11 \times {{10}^5}}} = \frac{1}{2}$
==>$n = 2$
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