Sudha finds out that the sharp image of the window pane of her science laboratory is formed at a distance of $15cm$ from the lens. She now tries to focus the building visible to her outside the window instead of the window pane without disturbing the lens. In which direction will she move the screen to obtain a sharp image of the building? What is the approximate focal length of this lens?

Q. Sudha finds out that the sharp image of the window pane of her science laboratory is formed at a distance of $15cm$ from the lens. She now tries to focus the building visible to her outside the window instead of the window pane without disturbing the lens. In which direction will she move the screen to obtain a sharp image of the building? What is the approximate focal length of this lens?

Q. Question 26
Sudha finds out that the sharp image of the window pane of her science laboratory is formed at a distance of 15 cm from the lens. She now tries to focus the building visible to her outside the window instead of the window pane without disturbing the lens. In which direction will she move the screen to obtain a sharp image of the building? What is the approximate focal length of this lens?

Q. While performing an experiment on determining the focal length of a convex lens, a student obtains a sharp inverted image of the laboratory window grill on the screen and measures the distance between the screen and the lens. She then repeats the experiment and takes a distant tree as the object in the second case. In order to get a sharp image of the tree on the screen, she will now have to move the screen:
(1) slightly nearer to the lens
(2) slightly farther away from the lens
(3) very close to the lens
(4) very far away from the lens

Q. A student obtained a sharp image of the grill of a window in the laboratory on a screen, using a convex lens. For getting better results, her teacher suggested focussing of a distant tree instead of the grill. In which direction should the lens be moved for this purpose to get a sharp image on the screen?
(1) Towards the screen
(2) Away from the screen
(3) Behind the screen
(4) Very far away from the screen

Q. A student obtained a sharp image of a lighted candle on the screen using a convex lens. Now he wants to focus a distant lamp on the screen. In which direction should the lens be moved for this purpose with respect to the screen, to get a sharp image on the screen?