According to Wein's law:
1. = constant
2. = constant
3. = constant
4. = constant
A black body has a maximum wavelength at a temperature of \(2000~\text K.\) Its corresponding wavelength at temperatures of \(3000~\text K\) will be:
1. | \(\dfrac{3}{2} \lambda_m\) | 2. | \(\dfrac{2}{3} \lambda_m\) |
3. | \(\dfrac{4}{9} \lambda_m\) | 4. | \(\dfrac{9}{4} \lambda_m\) |
A black body at \(200~\text{K}\) is found to emit maximum energy at a wavelength of \(14~\mu \text{m}\). When its temperature is raised to \(1000~\text{K}\), the wavelength at which maximum energy is emitted will be:
1. | \(14~\mu\text{m}\) | 2. | \(70~\mu\text{m}\) |
3. | \(2.8~\mu\text{m}\) | 4. | \(2.8~\text{nm}\) |
What is the ratio of the temperatures \(T_{1}\)
1. \(3:2\)
2. \(2:1\)
3. \(4:3\)
4. \(1:1\)
A piece of iron is heated in a flame. If it becomes dull red first, then becomes reddish yellow, and finally turns to white hot, the correct explanation for the above observation is possible by using:
1. | Stefan's law | 2. | Wien's displacement law |
3. | Kirchhoff's law | 4. | Newton's law of cooling |
If \(\lambda_m\) is the wavelength, corresponding to which the radiant intensity of a block is at its maximum and its absolute temperature is \(T,\) then which of the following graphs correctly represents the variation of \(T?\)
1. | ![]() |
2. | ![]() |
3. | ![]() |
4. | ![]() |
The plots of intensity versus wavelength for three black bodies at temperatures \(T_1,T_2\) and \(T_3\) respectively are as shown. Their temperatures are such that:
1. | \({T}_1>{T}_2>{T}_3 \) | 2. | \({T}_1>{T}_3>{T}_2 \) |
3. | \({T}_2>{T}_3>{T}_1 \) | 4. | \({T}_3>{T}_2>{T}_1\) |
The energy distribution E with the wavelength for the black body radiation at temperature T Kelvin is shown in the figure. As the temperature is increased the maxima will:
1. | Shift towards left and become higher |
2. | Rise high but will not shift |
3. | Shift towards right and become higher |
4. | Shift towards left and the curve will become broader |
A black body is at a temperature of 5760 K. The energy of radiation emitted by the body at a wavelength of 250 nm is U1, at a wavelength of 500 nm is U2 and that at 1000 nm is U3. Given Wien's constant of the following is correct?
1. U3=0
2. U1>U2
3. U2>U1
4. U1=0