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namnam03042k
2 năm trước
Cho 2 vật chuyển động tròn đều trên cùng đường tròn có chu vi 100(m) với tốc độ dài lần lượt là 10(m/s) và 15(m/s). Biết ban đầu 2 vật xuất phát từ cùng 1 vị trí và chuyển động ngược chiều nhau. Thời gian hai vật gặp nhau lần thứ 2( không kể lúc xuất phát) là: A. 4(s) B. 5(s) C. 10(s) D. 8(s)
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