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toanvinh43
2 năm trước
Một viên đạn khoi lượng 50 g đang bay ngang với vận tốc không đối 200 m/s tới đâm xuyên vào một tấm gỏ. Viên đạn xuyên qua tấm gỗ chỉ dày 2 cm và bay ra ngoài. a. Xác định lực cản trung bình của tấm gỏ tác dụng lên viên đạn? b. Vận tốc của viên đạn khi nó vừa bay ra khỏi tấm gỗ? ( Coi lực cản trung bình của gỗ là ng đối )
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