Home
Class 11
PHYSICS
Distribution of energy in the spectrum o...

Distribution of energy in the spectrum of a black body can be correctly represented by .

A

Stefan's law

B

Kirchoff's law

C

Planks's law

D

Wien's law

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the distribution of energy in the spectrum of a black body, we need to analyze the different laws related to black body radiation. ### Step-by-Step Solution: 1. **Understanding Black Body Radiation**: A black body is an idealized physical object that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence. The energy emitted by a black body is a function of its temperature and the wavelength of the radiation. 2. **Reviewing the Relevant Laws**: - **Stefan-Boltzmann Law**: This law states that the total energy emitted per unit surface area of a black body is proportional to the fourth power of its absolute temperature (T). The formula is given by: \[ E = \sigma T^4 \] where \(E\) is the total energy emitted, \(\sigma\) is the Stefan-Boltzmann constant, and \(T\) is the absolute temperature. However, this law does not provide the distribution of energy across different wavelengths. - **Kirchhoff's Law**: This law relates the emissive power of a body to its absorptive power at thermal equilibrium. It states that the emissive power of a body is equal to the absorptive power of a black body at the same temperature. This law does not describe the spectral distribution of energy. - **Planck's Law**: This law provides a formula for the spectral distribution of energy emitted by a black body at a given temperature. It states that the energy emitted per unit wavelength is given by: \[ E(\lambda, T) = \frac{2hc^2}{\lambda^5} \cdot \frac{1}{e^{\frac{hc}{\lambda kT}} - 1} \] where \(E(\lambda, T)\) is the energy emitted at wavelength \(\lambda\), \(h\) is Planck's constant, \(c\) is the speed of light, \(k\) is Boltzmann's constant, and \(T\) is the absolute temperature. This law accurately describes the distribution of energy across different wavelengths. - **Wien's Displacement Law**: This law states that the wavelength at which the emission of a black body spectrum is maximized is inversely proportional to the temperature. It is given by: \[ \lambda_{max} \cdot T = b \] where \(b\) is Wien's displacement constant. This law is also limited to the maximum wavelength and does not provide a complete spectral distribution. 3. **Conclusion**: Among the laws discussed, **Planck's Law** is the only one that correctly represents the distribution of energy in the spectrum of a black body across all wavelengths. Therefore, the correct answer to the question is **Planck's Law**. ### Final Answer: The distribution of energy in the spectrum of a black body can be correctly represented by **Planck's Law**.

To solve the question regarding the distribution of energy in the spectrum of a black body, we need to analyze the different laws related to black body radiation. ### Step-by-Step Solution: 1. **Understanding Black Body Radiation**: A black body is an idealized physical object that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence. The energy emitted by a black body is a function of its temperature and the wavelength of the radiation. 2. **Reviewing the Relevant Laws**: - **Stefan-Boltzmann Law**: This law states that the total energy emitted per unit surface area of a black body is proportional to the fourth power of its absolute temperature (T). The formula is given by: ...
Promotional Banner

Topper's Solved these Questions

  • CALORIMETRY AND HEAT TRANSFER

    DC PANDEY ENGLISH|Exercise Taking it together|51 Videos
  • CALORIMETRY AND HEAT TRANSFER

    DC PANDEY ENGLISH|Exercise Assertion and reason|17 Videos
  • CALORIMETRY AND HEAT TRANSFER

    DC PANDEY ENGLISH|Exercise Check points 16.3|20 Videos
  • CALORIMETRY & HEAT TRANSFER

    DC PANDEY ENGLISH|Exercise Level 2 Subjective|14 Videos
  • CENTRE OF MASS

    DC PANDEY ENGLISH|Exercise Medical entrances gallery|27 Videos

Similar Questions

Explore conceptually related problems

Name the law which helps us to explain the distribution of energy in the spectrum of a black body for (i) short wavelength only (ii) long wavelength only.

State Stefan's law and Wien's displacement law. Draw graphs showing the distribution of energy in the spectrum of a black body. Explain what quantity is plotted against the wavelength . By considering how this energy distribution varies with tempaerature expalin the colour changes which occur when a piece of iron is heated from cold to near the melting point.

State Stefan's law. Sketch graphs showing the distribution of energy in the spectrum of black body radiation at three temperatures, and indicate which curve corresponds to the highest temperature.

What is a black body ?

Structure of XeO_(2)F_(2) is correctly represented by

Structure of XeO_(2)F_(2) is correctly represented by

In the figure, the distribution of energy density of the radiation emitted by a black body at a given temperature is shown. The possible temperature of the black body is

The intestinal antiseptic Salol is correctly represented as:

The energy radiated by a black body is directly proportional to :

DC PANDEY ENGLISH-CALORIMETRY AND HEAT TRANSFER-Check points 16.4
  1. A hot and a cold body are kept in vacuum separated from each other. Wh...

    Text Solution

    |

  2. A body, which emits radiations of all possible wavelengths, is known a...

    Text Solution

    |

  3. Distribution of energy in the spectrum of a black body can be correctl...

    Text Solution

    |

  4. Which of the following law states that "good absorbers of heat are goo...

    Text Solution

    |

  5. The ratio of the Emissive power to the absorption power of all substan...

    Text Solution

    |

  6. If between wavelength lambda andlambda + dlambda, e(lambda) and a(lamb...

    Text Solution

    |

  7. There is a black spot on a body. If the body is heated and carried in ...

    Text Solution

    |

  8. In MKS system, Stefan's constant is denoted by sigma. In CGS system mu...

    Text Solution

    |

  9. A black body radiates 20 W at temperature 227^(@)C. If temperature of ...

    Text Solution

    |

  10. Two spherical black bodies of radii R(1) and R(2) and with surface tem...

    Text Solution

    |

  11. A sphere has a surface area of 1.0 m^(2) and a temperature of 400 K an...

    Text Solution

    |

  12. Two spheres of the same material have radii 1m and 4m and temperatures...

    Text Solution

    |

  13. The area of a hole of heat furnace is 10^(-4)m^(2). It radiates 1.58xx...

    Text Solution

    |

  14. If a body cools down from 80^(@) Cto 60^(@) C in 10 min when the tempe...

    Text Solution

    |

  15. A block of metal is heated to a temperature much higher than the room ...

    Text Solution

    |

  16. If wavelengths of maximum intensity of radiations emitted by the sun a...

    Text Solution

    |

  17. The maximum wavelength of radiation emitted at 200 K is 4 μm. What wil...

    Text Solution

    |

  18. The maximum energy in thermal radiation from a source occurs at the wa...

    Text Solution

    |

  19. The intensity of radiation emitted by the sun has its maximum value at...

    Text Solution

    |

  20. In the figure, the distribution of energy density of the radiation emi...

    Text Solution

    |