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dmxhna0131
2 năm trước
Một hệ gồm 2 vật có khối lượng m1= 6kg, m2=4kg đang chuyển động ngược chiều nhau với vật tốc lần lượt là v1= 2m/s, v2= 1m/s tới va chạm vào nhau. a) Xác định độ lớn động lượng của mỗi vật trước khi va chạm. b)Xác định độ lớn động lượng của hệ trước khi va chạm. c) Sau va chạm 2 vật dính vào nhau và chuyển động với cùng vận tốc. Tìm vận tốc đó.
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