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2 năm trước
Thả miếng chì 1300C trên vào chậu dựng nước có nhiệt độ 340C. Nhiệt độ khi có cân bằng nhiệt là 720C. Tính thể tích của nước? Coi như chỉ có nước và chì truyền nhiệt cho nhau. Biết nhiệt dung riêng của nước là 4200 J/kg.K, nhiệt dung riêng của chì là 130 J/kg.K.
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