Home
Class 12
PHYSICS
A body of surface are 15xx10^(-3)m^2 emi...

A body of surface are `15xx10^(-3)m^2` emits 0.3 kcal in 40 second at a temperature `70^(@)C`. The emissive power of the surface at that temperature is

A

`2.66kcal//m^2s`

B

`5.66xx10^(-3)kcal//m^2s`

C

`0.50kcal//m^2s`

D

`2.77xx10^(-3)kcal//m^2s`

Text Solution

Verified by Experts

The correct Answer is:
C
Promotional Banner

Topper's Solved these Questions

  • KINETIC THEORY OF GASES AND RADIATION

    TARGET PUBLICATION|Exercise Competitive thinking|187 Videos

  • KINETIC THEORY OF GASES AND RADIATION

    TARGET PUBLICATION|Exercise Evaluation test|18 Videos

  • KINETIC THEORY OF GASES AND RADIATION

    TARGET PUBLICATION|Exercise Evaluation test|18 Videos

  • INTERFERENCE AND DIFFRACTION

    TARGET PUBLICATION|Exercise EVALUATION TEST|20 Videos

  • MAGNETIC EFFECT OF ELECTRIC CURRENT

    TARGET PUBLICATION|Exercise EVALUATION TEST|19 Videos

Similar Questions

Explore conceptually related problems

Calculate the amount of heat radiated per second by a body of surface are 10 cm^(2) kept in thermal equilibrium in a roomat temperature 27^(@)C . The emissivity of the surface = 0.80 and Stefan's constant sigma ~= 6 xx 10^(-8) W//m^(2) K^(4)

Calculate the amount of heat radiated per second by a body of surface area 12cm^(2) kept in thermal equilibrium in a room at temperature 20^(@)C The emissivity of the surface =0.80 and sigma=6.0xx10^(-s)Wm^(-2)K^(-4) .

If the emissive power of a certain body at a certain temperature is 2000 W//m^(2) and the emissive power of a perfect blackbody at the same temperature is 10000 W//m^(2) , what is the coefficient of emission of the body ?

A body having a surface area of 50cm^2 radiates 300J of energy per minute at a temperature of 727^(@)C . The emissivity of the body is ( Stefan's constant =5.67xx10^(-8)W//m^2K^4 )

Radius of a calorimeter is r and depth is l . It is filled completely with water and then cooled from temperature theta in the surroundings at a temperature theta_(0) .If the emissive power of the surface of calorimeter is 1 and that of open surface of water is 0.5, then the ratio of rates of heat radiated by the surface of calorimeter and open surface of water will be –

An air bubble of volume 1.0 cm^(3) rises from the bottom of a take 40 m deep at a temperature of 12^(@) C . To what volume does it grow when it reaches the surface, which is at a temperature of 35^(@) C . ? Given 1 atm = 1.01 xx 10^(5) Pa .

TARGET PUBLICATION-KINETIC THEORY OF GASES AND RADIATION -critical thinking
  1. The rate of emission of heat energy per unit area of an iron ball of r...

    Text Solution

    |

  2. Emissive power of cube is 1000 J//m^2s and it · radiates heat at the r...

    Text Solution

    |

  3. A body of surface are 15xx10^(-3)m^2 emits 0.3 kcal in 40 second at a...

    Text Solution

    |

  4. A hot and a cold body are kept in vacuum separated from each other. Wh...

    Text Solution

    |

  5. Unit of Stefan's constant is

    Text Solution

    |

  6. If the temperature o fblack body decreases to half of the initial temp...

    Text Solution

    |

  7. If the temperature of a hot body is increased by 50%, then the increas...

    Text Solution

    |

  8. The temperatures of two bodies A and B are 727^(@)C and 127^(@)C . Th...

    Text Solution

    |

  9. A spherical black body with a radius of 20 cm radiates 440 W power at ...

    Text Solution

    |

  10. A body having a surface area of 50cm^2 radiates 300J of energy per min...

    Text Solution

    |

  11. At 127^(@)C radiated energy is 2.7 xx 10^(-3) J//s. At what temperatur...

    Text Solution

    |

  12. The rate of cooling at 600 K, if surrounding temperature is 300 K is R...

    Text Solution

    |

  13. Two solid spheres of radii R(1) and R(2) are made of the same material...

    Text Solution

    |

  14. A black body radiates 6 J//cm^2s when its temperature is 127 °C. How m...

    Text Solution

    |

  15. The ratio of masses of two metal spheres A and B is 8 : I. If their te...

    Text Solution

    |

  16. A hot liquid is kept in a big room. The logarithm of the numerical val...

    Text Solution

    |

  17. Rate of cooling of a body is 0 .2° C/min, when excess temperature is 2...

    Text Solution

    |

  18. A body cools at the rate of 0.75 °C/s, when it is 50 °C above the surr...

    Text Solution

    |

  19. A body cools at the rate of 0.75 °C/s, when it is 50 °C above the surr...

    Text Solution

    |

  20. A body takes 5 minutes for cooling from 50^(@)C to 40^(@)C Its temp...

    Text Solution

    |