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nguyenngocdai1507
2 năm trước
Một bếp điện tiêu thụ một công suất 2500W khi mắc vào hiệu điện thế 220V. Hãy tính: a. Cường độ dòng điện qua bếp và điện trở của bếp. b. Tính thời gian để bếpt đun sôi 2l nước từ 25oC, biết hiệu suất của bếp là 86% và nhiệt dung riêng của nước là 4800 J/ kg.0K.
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