Question
Physics Question on Ray optics and optical instruments
A convex lens ‘A’ of focal length 20 cm and a concave lens ‘B’ of focal length 5 cm are kept along the same axis with a distance ‘d’ between them. If a parallel beam of light falling on ‘A’ leaves ‘B’ as a parallel beam, then the distance ‘d’ in cm will be
A
30
B
25
C
15
D
50
Answer
15
Explanation
Solution
The correct answer is option (C): 15