The lens formula relating object distance (u), image distance (v), and focal length (f) is:
Q1. The lens formula relating object distance (u), image distance (v), and focal length (f) is:
Answer: 1/f = 1/v - 1/u
Explanation: The standard lens formula is 1/f = 1/v − 1/u, where f is the focal length, v is the image distance, and u is the object distance (negative for a real object using the real-is-positive sign convention). This formula applies to both converging and diverging thin lenses.