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Air bad conductor of heat, still vacuum ...

Air bad conductor of heat, still vacuum is preferred between the walls of the thermo flask because

A

it is difficult to fill the air between the walls of thermos flask

B

due to more pressure of air, the thermos can get crack

C

by convection, heat can flow through air

D

on filling the air, there is no advantage

Text Solution

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The correct Answer is:
C
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