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Thinthin2000
2 năm trước
1.Khi dùng một máy phát điện xoay chiều quay tay có tần số f = 5Hz để thắp sáng một đèn LED, ta thây đèn bật-tắt liên tục, tại sao? Nếu thay đèn LED bằng một đèn dây tóc bình thường thì đèn sẽ sáng như thế nào? 2.Người ta truyền tải một công suất điện 10kW bằng một đường dây dẫn có điện trở 4Ω thì công suất hao phí trên đường dây truyền tải điện là 0,1kW. Hiệu điện thế giữa hai đầu dây tải điện là bao nhiêu?
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