Answer: 1/f = 1/v - 1/u.
- A 1/f = 1/v - 1/u
- B 1/f = 1/v + 1/u
- C f = uv
- D 1/f = (n-1)(1/R<sub>1</sub> - 1/R<sub>2</sub>)
Correct answer: A. 1/f = 1/v - 1/u
Explanation: Lens formula: 1/v - 1/u = 1/f (New Cartesian convention).
Concave mirror ray construction: a ray parallel to the axis reflects through F, and a ray through F reflects parallel, locating the inverted real image. Image: Maxmath12, CC0, via Wikimedia Commons.
Concept context
Reflection, refraction, lenses, mirrors, total internal reflection.