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lqdat2009
2 năm trước

Một vật sáng AB đặt vuông góc với trục chính của thấu kính hội tụ, A nằm trên trục chính cho ảnh thật A’B’. Biết A’B’ = 3AB. a) Xác định quang tâm O, các tiêu điểm chính của thấu kính. b) Biết khoảng cách AA’ = 80 cm. Xác định vị trí của vật, của ảnh. Vẽ hình giúp tui với ahhhhhh

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Trương Tiến Nhật
2 năm trước

Ok

Nguyễn Ánh
2 năm trước

b, Ta có d/d'=h/h'=1/3

=>3d=d'<=>3d-d'=0(1)

ta có d+d'=80(2)

từ(1)và(2) ta có hpt:

3d-d'=0 

d+d'=80 

d=10

d'=30

 

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