For a Convex Lens, object can be kept at different positions Hence, we take different cases Case 1 - Object is Placed at infinity
In this Case, Object is kept far away from lens (almost at infinite distance) So, we draw rays parallel to principal axis Since ray parallel to principal axis passes through the Focus Both rays meet at focus after refraction Hence, Image is formed at F 2 And it is very very small We can say that
Here, Object AB is beyond 2F 1 First, we draw a ray parallel to principal axis So, it passes through focus after refraction We draw another ray which passes through Optical Center So, the ray will go through without any deviation And the image formed is A'B' This image is formed between F 2 and 2F 2 We can say that
Case 3 - Object is at 2F
Here, Object AB is at 2F 1 First, we draw a ray parallel to principal axis So, it passes through focus after refraction We draw another ray which passes through Optical Center So, the ray will go through without any deviation Where both refracted rays meet is point A' And the image formed is A'B' This image is formed at 2F 2 We can say that
Here, Object AB is kept between F 1 and 2F 1 First, we draw a ray parallel to principal axis So, it passes through focus after refraction We draw another ray which passes through Optical Center So, the ray will go through without any deviation Where both refracted rays meet is point A' And the image formed is A'B' This image is formed between beyond 2F 2 We can say that
Case 5 - Object is at F
Here, Object AB is kept at F 1 First, we draw a ray parallel to principal axis So, it passes through focus after refraction We draw another ray which passes through Optical Center So, the ray will go through without any deviation Hence we can say that they meet at infinity. Hence, the rays form an image at infinity And image formed would be larger than the object We can say that
Here, Object AB is kept between O and F 1 First, we draw a ray parallel to principal axis So, it passes through focus after refraction We draw another ray which passes through Optical Center So, the ray will go through without any deviation We observe that both refracted rays are diverging It means that they would have met at some point Hence, we extend both rays behind the lens We see that the rays form an image behind the lens (on the left side). So, the image is virtual And image formed would be larger than the object We can say that
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