Vật AB đặt trước một thấu kính hội tụ,vuông góc với trục chính,A nằm trên trục chính, chiều cao của vật là 3cm, tiêu cực của thấu kính là 12cm,khoảng cách từ AB đến thấu kính là 20cm. A) Dựng ảnh của AB qua thấu kính, cho biết tính chất của ảnh??? B) Tính khoảng cách từ ảnh đến thấu kính và độ cao của ảnh ???

Các câu hỏi liên quan

1. I have never met him before → It................................................................................................................................................. 2. I have never eaten this kind of food before → It is.............................................................................................................................................. 3. I’ve never seen this film before → This.............................................................................................................................................. 4. We’ve never drunk this kind of water before → This is........................................................................................................................................... 5. He’s never been to HCM city before → It is............................................................................................................................................... 6. It is the first time I’ve seen this man → I’ve............................................................................................................................................... 7. This is the first time he phoned me. → He has............................................................................................................................................ 8. This is the first time I’ve talked to her → I’ve................................................................................................................................................ 9. This is the first time Nam has used computer → Nam has......................................................................................................................................... 10. It is the first time Tom has sung → Tom has......................................................................................................................................... 11. Ba has never listened to classical music before → This is........................................................................................................................................ 12. Nam has never seen her before → It is............................................................................................................................................. 13. I have never talked to him before → It is............................................................................................................................................. 14. It is the first time Ba has killed chickens → Ba has........................................................................................................................................... 15. It is the first time she has eaten apples → She has.........................................................................................................................................