Một viên bi lăn từ đỉnh mặt phẳng nghiêng như hình...
Câu hỏi: Một viên bi lăn từ đỉnh mặt phẳng nghiêng như hình vẽ.
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)
Ở tại vị trí nào hòn bi có thế năng lớn nhất?
A. Tại A
B. Tại B
C. Tại C
D. Tại một vị trí khác
Câu hỏi trên thuộc đề trắc nghiệm
Trắc nghiệm Vật lý 8 bài 17: Sự chuyển hoá và bảo toàn công năng