To determine the approximate focal length of the  given convex lens by focusing on a distant object  (say, a sign board), you try to focus the image of  the object on a screen. The image you obtain on the  screen is always: 

(a) erect and laterally inverted  

(b) erect and diminished  

(c) inverted and diminished  

(d) virtual, inverted and diminished  



For a concave mirror

  • When the object is at infinity , the image is formed at the focus
  • This image is diminished
  • And it is also inverted



So, the correct answer is (c) - inverted and diminished



  1. Class 10
  2. Chapter 10 Class 10 - Light - Reflection and Refraction (Term 1)

About the Author

CA Maninder Singh's photo - Founder at Teachoo
CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo