Home
Class 12
PHYSICS
The rate of loss of heat from a body coo...

The rate of loss of heat from a body cooling under conditions of forced convection is proportional to its
(1) surface area
(2) excess of temperature over that of surrounding
(3) heat capacity
(4) absolute temperature

A

1, 2 and 3 are correct

B

1 and 2 are correct

C

2 and 4 are correct

D

1 and 3 are correct

Text Solution

Verified by Experts

Promotional Banner

Topper's Solved these Questions

Similar Questions

Explore conceptually related problems

The relation between rate of loss of heat from the body and its absolute temperature is known as

Ac cording to Newton's law of cooling, the rate of cooling of a body is proportional to (Delta theta)^(n) , where Delta theta is the difference of the temperature of the body and thae surrounding. What is the value of n out of 4,3,2,and 1?

According to Newton’s law of cooling, the rate of cooling of a body is proportional to (Deltatheta)^(n) , where Deltatheta is the difference of the temperature of the body and the surrounding, and n is equal to :

The rate of loss of heat by radiation from a body at 400^(@)C is R. The radiation from it when the temperature rises to 800^(@)C ?

Assertion: According to Newton's law of cooling, the rate of loss of heat, -dQ//dt of the body is directly proportional to the difference of temperature. Reason :This law holds for all type of temperature differences.

According to Newton's law of cooling, the rate of cooling of a body is proportional to (Delta theta)^n , where Delta theta is the difference of the temperature of the body and the surroundings, and n is equal to

Assertion : Bodies radiate heat at all temperatures. Reason : Rate of radiation of heat is proportional to the fourth power of absolute temperature.

Newton’s law of cooling says that the rate of cooling of a body is proportional to the temperature difference between the body and its surrounding when the difference in temperature is small. (a) Will it be reasonable to assume that the rate of heating of a body is proportional to temperature difference between the surrounding and the body (for small difference in temperature) when the body is placed in a surrounding having higher temperature than the body? (b) Assuming that our assumption made in (a) is correct estimate the time required for a cup of cold coffee to gain temperature from 10^(@)C to 15^(@)C when it is kept in a room having temperature 25^(@)C . It was observed that the temperature of the cup increases from 5^(@)C to 10^(@)C in 4 min

DISHA-HEAT TRANSFER AND NEWTONS LAW OF COOLING-physics
  1. A solid copper sphere (density rho and specific heat c) of radius r at...

    Text Solution

    |

  2. Four rods of identical cross-sectional area and made from the same met...

    Text Solution

    |

  3. Consider two hot bodies B(1) and B(2) which have temperature 100^(@)"C...

    Text Solution

    |

  4. A body cools from 60^@C to 50^@C in 10 min. Find its temperature at ...

    Text Solution

    |

  5. The rates of cooling of two different liquids put in exactly similar c...

    Text Solution

    |

  6. For cooking the food, which of the following type of utensil is most s...

    Text Solution

    |

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

    Text Solution

    |

  8. While measuring the thermal conductivity of liquids the upper part is ...

    Text Solution

    |

  9. When fluids are heated from the bottom, convection currents are produc...

    Text Solution

    |

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

    Text Solution

    |

  11. Two thermometers A and B are exposed in sunlight. The bulb of A is pai...

    Text Solution

    |

  12. Two bodies A and B have thermal emissivities of 0.01 and 0.81 respecti...

    Text Solution

    |

  13. A cane is taken out from a refrigerator at 0^(@)"C". The atmospheric t...

    Text Solution

    |

  14. The rate of loss of heat from a body cooling under conditions of force...

    Text Solution

    |

  15. A brass ball of mass 100g is heated to 100^(@)"C" and then dropped int...

    Text Solution

    |

  16. A brass ball of mass 100g is heated to 100^(@)"C" and then dropped int...

    Text Solution

    |

  17. A brass ball of mass 100g is heated to 100^(@)"C" and then dropped int...

    Text Solution

    |

  18. Assertion : The equivalent thermal conductivity of two plates of same ...

    Text Solution

    |

  19. Assertion : Coefficient of absorption of radiation of an ideal black ...

    Text Solution

    |

  20. Statement-1 : As temperature of a black body is raised, wavelenght cor...

    Text Solution

    |