The silvering in thermos flasks is done to avoid heat transfer by:
[amp_mcq option1=”Convection” option2=”Conduction” option3=”Radiation” option4=”Both convection and conduction” correct=”option3″]
This question was previously asked in
UPSC NDA-2 – 2015
– The vacuum between the double walls reduces heat transfer by conduction and convection.
– The stopper reduces convection (and some conduction).
– The silvered surfaces (typically vacuum-deposited aluminum) on the inner and outer walls are poor emitters and excellent reflectors of thermal radiation. This significantly reduces heat transfer by radiation across the vacuum.