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anhvan2002
2 năm trước
Một vật trượt từ đỉnh A của 1 mặt phẳng nghiêng không ma sát có độ cao 0,8m . Sau khi tới chân mặt phẳng nghiêng tại B , vật tiếp tục đi trên mặt phẳng ngang 1 đoạn 0,4m mới dừng lại tại C do ma sát, cho g=10m/s. Dùng phương pháp năng lượng tìm: a) Vận tốc của vật tại điểm D giữa mặt phẳng nghiêng và tại điểm B ở chân mặt phẳng nghiêng b) Quãng đưởng BC Mọi người ơi giúp em với mai em kiểm tra rồi :((((
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