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A heated body emits radiation which has ...

A heated body emits radiation which has maximum intensity near the frequency `v_(0)` The emissivity of the material is `0.5` . If the absolute temperature of the body is doubled,

A

the maximum intensity of radiation will be near the frequency `2v_(0)`

B

the maximum intensity of radiation will be near the frequency `v_(0)/2`

C

the total energy emitted will increases by a factor of `16`

D

the total energy emitted will increases by a factor of `8`.

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To solve the problem step by step, we will analyze the effects of doubling the absolute temperature of a heated body on the frequency of maximum intensity of radiation emitted and the total energy emitted. ### Step 1: Understanding Wien's Displacement Law Wien's Displacement Law states that the product of the wavelength of maximum intensity (λ_max) and the absolute temperature (T) of a black body is a constant. Mathematically, it is expressed as: \[ \lambda_{max} \cdot T = b \] where \( b \) is Wien's displacement constant. ### Step 2: Relating Wavelength and Frequency The relationship between wavelength (λ) and frequency (ν) is given by: \[ \lambda = \frac{c}{\nu} \] where \( c \) is the speed of light. Therefore, we can express the maximum wavelength in terms of frequency: \[ \lambda_{max} = \frac{c}{\nu_{max}} \] This means we can relate the maximum frequency and temperature using the displacement law. ### Step 3: Setting Up the Initial and Final Conditions Let: - \( T_1 \) be the initial temperature - \( T_2 = 2T_1 \) be the final temperature after doubling - \( \nu_1 \) be the initial frequency of maximum intensity - \( \nu_2 \) be the final frequency of maximum intensity From Wien's law, we have: \[ \lambda_{1} \cdot T_1 = \lambda_{2} \cdot T_2 \] ### Step 4: Expressing Frequencies in Terms of Temperatures Using the relationship between wavelength and frequency, we can write: \[ \frac{c}{\nu_1} \cdot T_1 = \frac{c}{\nu_2} \cdot T_2 \] Cancelling \( c \) from both sides gives: \[ \frac{T_1}{\nu_1} = \frac{T_2}{\nu_2} \] Rearranging this gives: \[ \frac{\nu_2}{\nu_1} = \frac{T_2}{T_1} \] ### Step 5: Substituting the Temperature Values Substituting \( T_2 = 2T_1 \) into the equation: \[ \frac{\nu_2}{\nu_1} = \frac{2T_1}{T_1} = 2 \] This implies: \[ \nu_2 = 2\nu_1 \] ### Step 6: Conclusion on Maximum Frequency Thus, when the absolute temperature is doubled, the frequency of maximum intensity of radiation emitted by the body becomes: \[ \nu_2 = 2\nu_0 \] where \( \nu_0 \) is the initial frequency. Therefore, the maximum intensity of radiation will be near the frequency \( 2\nu_0 \). ### Step 7: Analyzing Total Energy Emitted According to the Stefan-Boltzmann Law, the total energy emitted by a black body is proportional to the fourth power of its absolute temperature: \[ E \propto T^4 \] If we denote the initial energy as \( E_1 \) at temperature \( T_1 \) and the final energy as \( E_2 \) at temperature \( T_2 \): \[ \frac{E_2}{E_1} = \left(\frac{T_2}{T_1}\right)^4 = \left(\frac{2T_1}{T_1}\right)^4 = 2^4 = 16 \] Thus, the total energy emitted will increase by a factor of 16. ### Final Answers 1. The maximum intensity of radiation will be near the frequency \( 2\nu_0 \). 2. The total energy emitted will increase by a factor of 16.

To solve the problem step by step, we will analyze the effects of doubling the absolute temperature of a heated body on the frequency of maximum intensity of radiation emitted and the total energy emitted. ### Step 1: Understanding Wien's Displacement Law Wien's Displacement Law states that the product of the wavelength of maximum intensity (λ_max) and the absolute temperature (T) of a black body is a constant. Mathematically, it is expressed as: \[ \lambda_{max} \cdot T = b \] where \( b \) is Wien's displacement constant. ### Step 2: Relating Wavelength and Frequency ...
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