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The temperature of our Sun鈥檚 surface is ~6000K.(a) At what wavelength is the spectral emission of the Sun is maximum? (Refer to Exercise 79.) (b) Is there something conspicuous about this wavelength?

Short Answer

Expert verified

(a) The wavelength at which the spectral emission is maximum is4.82810-7m .

(b) It is conspicuous as it is in the visible range of the spectrum.

Step by step solution

01

Given data

Given data can be listed below as:

The temperature of the sun is, T=6000K.T=6000K.

02

Wein’s displacement law

The law gives the relationship between the maximum wavelength of the radiation that was released from a black body and the temperature at which the black body was kept; this relationship can be expressed as,

maxT=b (1)

Here maxis the maximum wavelength, localid="1660183413143" Tis the temperature at which the black body was kept, and localid="1660183425059" bis known as Wien鈥檚 displacement constant.

03

a) Determination of Wavelength for the maximum temperature of the sun

Let鈥檚 modify equation 1 as,

max=bT (2)

The value of Wien鈥檚 displacement constant is, b=2.89710-3mK.

The wavelength at which the spectral emission of the Sun is maximum can be calculated from the above expression. The maximum spectral emission is associated with the maximum wavelength (peak in the energy-temperature curve) for that given temperature.

Substitute the values in equation 2, and we get,

max=2.89710-3mK6000K=4.82810-7m

Thus, the wavelength at which the spectral emission is maximum is 4.82810-7m.

04

b) Conspicuous about this wavelength

From the calculation of part a, the wavelength at which the spectral emission is maximum is 4.82810-7m.

The visible spectrum exists between 300nmand 700nm.

The wavelength we calculated in nm can be calculated as,

=4.82810-7m=4.82810-71m109nm1m=4.82810-7109nm=4.828102nm=482.8nm

This is between the visible range in the middle, to be precise.

Thus, it is conspicuous as it is in the visible range of the spectrum.

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