Q: Why does a liquid remain hot or cold for a long time inside a thermos flask?
Answer: Do you know that thermos flask has double glass wall? The air is trapped in between this double wall of glass. When a liquid hot or cold is put into a thermos then this air does not allow the heat to loose through it. Do you know why? Yes, you are right, because the air is an insulator or poor conductor of heat.
This is the only simple reason that trapped air in double glass will not allow the heat to loose and this is the reason that a liquid remain hot or cold for a long time inside a thermos.
Q: Why is cooking quicker in a pressure cooker? Continue reading “Common daily life science queries – 1”