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hungphandinh030420
2 năm trước
Một vật khối lượng 2kg đang chuyển động với vận tốc 25m/s thì trượt lên dốc. Biết dốc dài 50m, đỉnh dốc cao 14m, hê số ma sát giữa vạt và mặt dốc là 0,25. Cho g=10m/s2. a, Tính công trọng lực, công của lực ma sát b, Tính vận tốc của vật ở đỉnh dốc
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