The distance between an object and a convex lens is changing, and it is noticed that the size of the image formed on a screen is decreasing. Is the object moving in a direction towards the lens or away from it?

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Solution

Since the question is talking about an image on a screen, we can understand that its a real image.

In the case of a convex lens, when we move the object away from the lens, the size of the real image decreases. Ultimately when an object is at an infinite distance, a real point sized image is formed at the focus of the lens.

Therefore we can say that the object is moving away from the lens.

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