Physics
Physics
Problem
A converging lens of focal length is used as a simple magnifier so that the final image is formed at infinity. Taking the least distance of distinct vision , calculate its magnifying power (angular magnification).Intuitive explanation
When a magnifier produces an image at infinity, your eye is relaxed and viewing the magnified object at its most comfortable angle. The key insight is comparing two scenarios: how large the object appears to your naked eye versus through the lens. The magnifying power is the ratio of the angle subtended by the magnified image to the angle subtended by the object placed at the near point—and this ratio simplifies beautifully to when the final image is at infinity.
Intuitive explanation
When a magnifier produces an image at infinity, your eye is relaxed and viewing the magnified object at its most comfortable angle. The key insight is comparing two scenarios: how large the object appears to your naked eye versus through the lens. The magnifying power is the ratio of the angle subtended by the magnified image to the angle subtended by the object placed at the near point—and this ratio simplifies beautifully to when the final image is at infinity.