question_answer

Two thermos flasks are of the same height and same capacity. One has a circular cross section while the other has a square cross-section. Which of the two is better?

Answer:

                As both flasks have same height and capacity, the area of the cylindrical wall will be less than that of the square wall. Hence the thermos flask of circular cross-section will transmit less heat as compared to the thermos flask of square cross-section and will be better.