Physics, 26.06.2021 15:40 gabriella1232002

1. Một vật nặng 513g trượt từ đỉnh mặt phẳng nghiêng cao 9m, biết góc nghiêng hợp phương ngang 30° và hệ số ma sát giữa vật và mặt phẳng nghiêng là 0,28 , lấy g = 10m/s2. Hãy xác định: a. Gia tốc của vật? (1 điểm – hình vẽ: 0,5 điểm) b. Động năng của vật khi chạm đất. ( 1 điểm) c. Công của trọng lực tác dụng lên vật khi trượt trên mặt phẳng nghiêng. (1 điểm) d. Biết hệ số ma sát giữa vật và mặt phẳng ngang là 0,19 . Tính công của lực ma sát tác dụng lên vật khi trượt trên mặt phẳng ngang. (1 điểm – hình vẽ: 0,5 điểm).

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1. Một vật nặng 513g trượt từ đỉnh mặt phẳng nghiêng cao 9m, biết góc nghiêng hợp phương ngang 30° v...

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