Wien’s Displacement Law

Following graphs show the variation in the intensity of heat radiations by the black body and frequency at a fixed temperature. Choose the correct option.

Solar radiation emitted by sun corresponds to that emitted by the black body at a temperature of $6000 \mathrm{K}$. Maximum intensity is emitted at a wavelength of $4800$$\stackrel{\circ }{\mathrm{A}}$. If the sun was to cool down from $6000 \mathrm{K}$to $3000 \mathrm{K}$, then the peak intensity of emitted radiation would occur at a wavelength

A black body is at temperature $2880 \mathrm{K}$. The energy of radiation emitted by the body at wavelength $250 \mathrm{nm}$ is $U_1$, at wavelength $500 \mathrm{nm}$ is $U_2$ and that of $1000 \mathrm{nm}$ is $U_3$. Then the correct answer is $($Weins constant $\left.b=2.88\times {10}^6 \mathrm{nmK}\right)$

Solar radiation has maximum intensity at a wavelength of $480 \mathrm{nm}$ in the visible region. Figure out the surface temperature of the sun using this information. (Use Wien's constant $b=2.88\times {10}^{-3} \mathrm{m}\mathrm{ }\mathrm{K}$)

If ${\lambda }_{\mathrm{m}}$ denotes the wavelength at which a certain black body radiates maximum intensity for a temperature $T \mathrm{K}$. Then the correct relation will be

The ratio of temperatures of two stars is $3:2$. If the wavelength of maximum intensity of the first star is $4000 \stackrel{\circ }{\mathrm{A}}$, what is the corresponding wavelength of the second star?

If the power radiated by three discs $\mathrm{A},\mathrm{B}$ and $\mathrm{C}$ having radii $2 \mathrm{m}, 4 \mathrm{m}$ and $6 \mathrm{m}$ are ${\text{Q}}_{\text{A}}{\text{,\hspace{0.17em}\hspace{0.17em}Q}}_{\text{B}}$ and ${\text{Q}}_{\text{C}}$ respectively and are coated with carbon black on their outer surfaces. The wavelength corresponding to their maximum intensities are $300 \mathrm{nm}, 400 \mathrm{nm}$ and $500 \mathrm{nm}$ respectively.Then,
 

A black body emits radiations of maximum intensity at $5000 \stackrel{\circ }{\mathrm{A}}$ when its temperature is $1227°\mathrm{C}$. If, its temperature is increased by $1000°\mathrm{C}$  then the maximum intensity of emitted radiation will be at:

The wavelength of maximum intensity of radiation emitted by a star is $289.8\mathrm{ }\mathrm{n}\mathrm{m}$. The radiation intensity of the star is
(Stefan's constant $=5.67\times {10}^{-8} \mathrm{W} {\mathrm{m}}^{-2} {\mathrm{K}}^{-4},$Wien's constant $=b=2898\mathrm{ }\mathrm{\mu }\mathrm{m}\mathrm{ }\mathrm{K}$) 

Experimental investigation shows that the intensity of solar radiation is maximum for a wavelength $480 \mathrm{nm}$ in the visible region. Estimate the surface temperature of sun. (Given Wien's constant $b=2.88\times {10}^{-3} \mathrm{m}\mathrm{ }\mathrm{K}$)

Generally the temperature of a distant star is estimated using

The earth radiates in the infra-red region of the spectrum. The spectrum is correctly given by

The black body spectrum of an object $Q_1$ is such that its radiant intensity (i.e., intensity per unit wavelength interval) is maximum at a wavelength of 100 nm. Another object $O_2$ has the maximum radiant intensity at 600 nm. The ratio of power emitted per unit area by source $O_1$ to that of source $O_2$ is

According to Wien's law

Following graphs show the variation in the intensity of heat radiations by the black body and frequency at a fixed temperature. Choose the correct option.

The spectral energy distribution of the Sun (temperature$=6050 \mathrm{K}$) has a maximum at $4753 \mathrm{\AA }$. The temperature of a star for which this maximum is at $9506 \mathrm{\AA }$ is

Following graph shows the correct variation in intensity of heat radiations by black body and frequency at a fixed temperature

Following graph shows the correct variation in intensity of heat radiations by black body and frequency at a fixed temperature

On observing light from three different stars P,Q and R, it was found that intensity of violet colour is maximum in the spectrum of P, the intensity of green colour is maximum in the spectrum of R and the intensity of red colour is maximum in the spectrum of Q. If ${\mathrm{T}}_{\mathrm{p}},\mathrm{ }{\mathrm{T}}_{\mathrm{Q}}$ and ${\mathrm{T}}_{\mathrm{R}}$ are the respective absolute temperatures of P, Q and R, then it can be concluded from the above observations that :

Assertion: The temperature of a red-hot body is lower than that of a white-hot body.

Reason: This follows from Wien's displacement law $:\mathrm{ }{\mathrm{\lambda }}_{\mathrm{m}}\mathrm{ }.\mathrm{ }\mathrm{T}\mathrm{ }=\mathrm{ }\mathrm{c}\mathrm{o}\mathrm{n}\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{n}\mathrm{t}$ .