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nguyenquanvn2004
1 năm trước
Một điểm sáng S ở trong nước, cách mặt nước 1 khoảng là HS = 40 cm phát ra 1 chùm tia sáng hẹp tới gặp mặt phân cách tại I với góc tới rất nhỏ.Tia sáng truyền theo phương IR ra không khí. Chiết suất của nước là 4/3. a. Tìm khoảng cách giữa ảnh S’ và S. b. Một người cao 180 cm và nhìn thấy hòn sỏi A dưới đáy hồ dường như cách mặt nước 120 cm. Hỏi nếu đứng xuống hồ thì người ấy có ngập đầu không?
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