Air is bad conductor of heat or partly conducts heat, still vacuum is – McqOptions

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1.	Air is bad conductor of heat or partly conducts heat, still vacuum is to be placed between the walls of the thermos 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
Answer» D. On filling the air, there is no advantage

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