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Use the formula lambda(m)T=0.29 cm K to ...

Use the formula `lambda_(m)T=0.29` cm K to obtain the characteristic temperature ranges for different parts of the electromagnetic spectrum. What do the numbers that you obtain tell you ?

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A body at temperature T produces a continous spectrum of wavelengths. For a black body, the wavelength corresponding to maximum intensity of radiation is given according to Planck.s law by the relation : `lambda_(m)T=0.29` cm K. For `lambda_(m)=10^(-6)` m, T = 2900 K. Using the same relation, temperatures for other wavelength can be found. These numbers tell us the temperature ranges required for obtaining radiations in different parts of the electromagnetic spectrum. Thus, to obtain visible radiation, say `lambda =5xx10^(-7)m`, the source should have a temperature of about 6000 K.
Note a lower temperature will also produce this wavelength but not of maximum intensity.
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