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ly66657
2 năm trước
Một chiếc trực thăng khối lượng m = 3 tấn, bay lên thẳng đều với vận tốc 54km/h. Tính công do lực nâng thực hiện trong 1 phút. Bỏ qua lực cản không khí. Lấy g 10m/ s ^2
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