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ngocloan2k1
2 năm trước
Một chậu sắt có thể tích 0,08dm3 chứa 2 lít nước ở 200C. Người ta bỏ vào đó 1 quả cầu bằng đồng có khối lượng 1 kg ở 1000C. Biết khối lượng riêng của sắt là 7800 kg/m3 ; nhiệt dung riêng của sắt, nước và đồng lần lượt là 460 J/(kg.K), 4200 J/(kg.K), 380 J/(kg.K). Bỏ qua hao phí nhiệt, tính nhiệt độ khi có sự cân bằng nhiệt.
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