Dùng hai lực có cùng độ lớn cùng Phương kéo hai vật m1 m2cùng chuyển động không ma sát trên mặt phẳng nằm ngang .biết ban đầu hai vật đều đứng yên.Sau khi cùng đi được quãng đường là s thì hai vật đạt vận tốc tương ứng là v1 v2.Chọn phát biểu đúng A. m1/m2= v2/v1 B. m1/m2= v2 bình/ v1 bình C. m1/m2= v1/v2 Đ. m1/m2= v1 bình / v1 bình

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