Question

3 students measured the focal lenght of a convex lens using parallel rays from a distant object. All of them measured the distance between the len and the inverted image on the screen

Student A saw a sharp image on the screen and labelled the distance as f1

student B saw a slightly larger blurred image on the screen and labelled the distance as f2

student C saw a slightly smaller blurred image on the screen and labelled the distance as f3

the relation between the three measurement would likely be:

(a) f1=f2=f3 (b) f1
give proper explanation also :)

Answer 1

All of them measured the distance between the len and the inverted image on ... student B saw a slightly larger blurred image on the screen and labelled