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Natural convection is not possible on:

Natural convection is not possible on: Correct Answer Orbiting satellite

CONCEPT:

Convection:

  • The mode of transfer of heat by means of migration of material particles of medium is called convection.
  • It is of two types:
    1. Natural convection
    2. Forced convection


Characteristics of convection:

  1. Natural convection takes place from bottom to top while forced convection in any direction.
  2. In the case of natural convection, convection currents move warm air upwards and cool air downwards. That is why heating is done from the base while cooling from the top.
  3. Natural convection plays an important role in ventilation, in changing climate and weather, and informing land and sea breezes and trade winds.
  4. Natural convection is not possible in a gravity-free region such as a free-falling lift or an orbiting satellite.
  5. The force of blood in our body by heart helps in keeping the temperature of the body constant.
  6. If liquids and gases are heated from the top (so that convection is not possible) they transfer heat (from top to bottom) by conduction.
  7. Mercury through a liquid is heated by conduction and not by convection.


EXPLANATION:

  • As we know that natural convection is not possible in a gravity-free region such as a free falling lift or an orbiting satellite. Hence, option 2 is correct.

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