49. Three thin lenses with focal lengths 0.1 m, 0.2 m, and 0.3 m are placed next to each other. What
問題詳情
49. Three thin lenses with focal lengths 0.1 m, 0.2 m, and 0.3 m are placed next to each other. What is the equivalent focal length of asingle lens? (A) 0.05 m (B) 0.15 m (C) 0.25 m (D) 0.33 m (E) 0.45 m