MHT CET 2022 Physics question
A convex lens 'A' of focal length 20 cm and a concave lens 'B' of focal length 56 cm are kept along the same axis with the distance 'd' between them. If a parallel beam of light falling on A leaves B as a parallel beam, then the magnitude of distance d (in cm) is
Answer: (B)
Solution
For a parallel beam to emerge parallel after passing through two coaxial thin lenses, the lenses must be separated so that the second focal point of the first lens coincides with the first focal point of the second lens (an afocal combination). For a convex lens cm and a concave lens cm
See the full step-by-step solution
Create a free account to read the complete working, and practise questions like this in a timed test.
Create a free account