Question

A converging lens of focal length $f_1$ is placed in front of and coaxially with the convex mirror of focal length $f_2$.Their separation is d. A parallel beam of light incident on the lens returns as a parallel beam from the arrangement

• A. The beam diameters of the incident and reflected beams must be the same
• B. $d=|f_1|-2|f_2|$
• C. $d=|f_2|-|f_1|$
• D. If the entire arrangement immersed in water, the conditions will remain unaltered

Answer 1

Answer: (A), (B)

The correct options are
A The beam diameters of the incident and reflected beams must be the same
B $d=|f_1|-2|f_2|$