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Tuyetda83
2 năm trước
Một ấm điện bằng nhôm có KL 0,5kg chứa 1kg nc ở n độ 20 độ C. Ng ta đổ thêm m(g) nước ở n độ 60 độ C vào ấm thì n độ khi cân = nht là 36,8 độ c. Bt rằng nht dung riêng của nước và nhôm lần lượt là 4200J/Kg.K và 880J/Kg.K ( Bỏ qua phần nht lượng tỏa ra ngoài m trường và coi như phần điện năng chuyển hóa hoàn toàn thành nht lượng) a) Tính KL nước đã đổ thêm vào ấm b) Muốn đun sôi lượng nc trong ấm trên trong 20p thì ấm điện phải có công suất là bnhiu? ( Câu b mong mọi người giải thích kĩ dùm mình nhé , mk chưa hiểu câu b lắm)
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