Trong môn trượt tuyết, một vận động viên sau khi trượt trên đoạn đường dốc thì trượt ra khỏi dốc theo phương ngang ở độ cao 100 m so với mặt đất. Người đó bay xa được 180 m trước khi chạm đất. Hỏi tốc độ của vận động viên đó khi rời khỏi dốc là bao nhiêu? Lấy g = 9,8 m/s2.
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- Thời gian rơi của vận động viên: $t = \sqrt{\frac{2h}{g}} = \sqrt{\frac{2 \cdot 100}{9.8}} \approx 4.52 s$
- Tầm xa của vận động viên: $L = v_0 t$
- Suy ra vận tốc ban đầu: $v_0 = \frac{L}{t} = \frac{180}{4.52} \approx 39.82 m/s$
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