Optics Question 1000
Question: Two coherent monochromatic light beams of intensities I and 4I are superposed. The maximum and minimum possible intensities in the resulting beam are
[IIT-JEE 1988; RPMT 1995; AIIMS 1997; MP PMT 1997;MP PET 1999; BHU 2002; KCET 2000, 05]
Options:
A) 5I and I
B) 5I and 3I
C) 9I and I
D) 9I and 3I
Show Answer
Answer:
Correct Answer: C
Solution:
$ {I _{\max }}={{(\sqrt{I _{1}}+\sqrt{I _{2}})}^{2}}={{(\sqrt{I}+\sqrt{4I})}^{2}}=9I $
$ {I _{\min }}={{(\sqrt{I _{1}}-\sqrt{I _{2}})}^{2}}={{(\sqrt{I}-\sqrt{4I})}^{2}}=I $
