Home
Class 11
PHYSICS
Calculate the amount of heat radiated pe...

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)`

Text Solution

Verified by Experts

`u = e sigma A T^(4)`
`= 0.8 xx 6 xx 10^(-8) x 10 xx 10^(-4) (27 + 273)^(4)`
`= 78 xx 10^(-12) xx 81 xx 18^(8)`
`= 0.39 W`
Promotional Banner

Topper's Solved these Questions

  • HEAT TRANSFER

    CP SINGH|Exercise Exercises|94 Videos

  • HEAT AND CALORIMETRY

    CP SINGH|Exercise Exercise|37 Videos

  • KINETIC THEORY OF GASES

    CP SINGH|Exercise Exercises|79 Videos

Similar Questions

Explore conceptually related problems

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) .

A room heater is made up of thin wall tubes of copper, each 1.0 m long and 4.0 cm in diameter. Hot water aet 77^(@)C circulates constantlyh through the tubes. Calculate the amount of heat radiated per second in a room where the average temperature is 27^(@)C . The emissivity of copper =0.8 and Stefan's contant =5.67xx10^(-8)Wm^(-2)K^(-1)

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 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 )

Calculate the maximum amount of heat which may be lost per second by radiation by a sphere 14cm in diameter at a temperature of 227^(@)C , when placed in an enclosure at 27^(@)C . Given Stefan's constant = 5.7 xx 10^(-8)Wm^(-2)K^(-4) .

A metal ball of surface area 200 cm^(2) and temperature 527^(@)C is surrounded by a vessel at 27^(@)C . If the emissivity of the metal is 0.4, then the rate of loss of heat from the ball is (sigma = 5.67 xx10^(-8)J//m^(2)-s-k^(4))

The energy of 6000 J is radiated in 10 minutes by a body of surface area 200 cm^(2) . Find the emissive power of the body.

A body which has a surface area 5.00 cm^(2) and a temperature of 727^(@)C radiated 300 j of energy each minute. What is the emissivity of body? Steafan's constant =5.67xx10^(-8) Wm^(-2) K^(-4) .

A body of surface area 10 cm^(2) and temperature 727 ^(@) C emits 600 J of enrgy per minute. Find its emissivity.

CP SINGH-HEAT TRANSFER-Exercises
  1. Calculate the amount of heat radiated per second by a body of surface ...

    Text Solution

    |

  2. When two ends of a rod wrapped with cotton are maintained at differenc...

    Text Solution

    |

  3. The thermal conductivity of a rod depends on

    Text Solution

    |

  4. One end of a metal rod is kept in a furnace. In steady state, the temp...

    Text Solution

    |

  5. In a room containing air, heat can go from one place to another

    Text Solution

    |

  6. The two ends of uniform rod of thermal conductivity K are maintained a...

    Text Solution

    |

  7. Which of the following circular rods (given radius r and length l) eac...

    Text Solution

    |

  8. Two rods A and B are of equal lengths. Their ends of kept between the ...

    Text Solution

    |

  9. The temperature gradient in a rod of 0.5 m length is 80^(@)C//m. It th...

    Text Solution

    |

  10. A cylindrical rod having temperature T(1) and T(2) at its ends. The ra...

    Text Solution

    |

  11. The heat is flowing through two cylinderical rods of same material. Th...

    Text Solution

    |

  12. Two identical vessels are filled with equal amounts of ice. The vessel...

    Text Solution

    |

  13. One end of a themally insulated copper rod of length 1 m long and of 1...

    Text Solution

    |

  14. A glass window conducts out a certain quantity of heat per second when...

    Text Solution

    |

  15. Two walls of thicknes l(1) and l(2) and ther-mal condctivities K(1) an...

    Text Solution

    |

  16. A slab consists of two layers of different materials of the same thick...

    Text Solution

    |

  17. Two rods of the same length and diameter, having thermal conductivitie...

    Text Solution

    |

  18. Consider a compound slab consisting of two different material having e...

    Text Solution

    |

  19. A cylinder of radius R made of a material of thermal conductivity K1 i...

    Text Solution

    |

  20. A long metallic bar is carrying heat from one of its ends to the other...

    Text Solution

    |

  21. A and B are two points on uniform metal ring whose centre is O The ang...

    Text Solution

    |