Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
Two coherent sources whose intensity ratio is $64: 1$ produce interference fringes. The ratio of intensities of maxima and minima is
PhysicsWave OpticsTS EAMCETTS EAMCET 2010
Options:
  • A $9: 7$
  • B $8: 1$
  • C $81: 49$
  • D $81: 7$
Solution:
1731 Upvotes Verified Answer
The correct answer is: $81: 49$
The ratio of intensities of maxima and minima
$\frac{I_{\max }}{I_{\min }}=\frac{\left(\sqrt{I_1}+\sqrt{I_2}\right)^2}{\left(\sqrt{I_1}-\sqrt{I_2}\right)^2}$
$=\frac{(\sqrt{64}+\sqrt{1})^2}{(\sqrt{64}-\sqrt{1})^2}$
$\frac{I_{\max }}{I_{\min }}=\frac{(8+1)^2}{(8-1)^2}=\frac{81}{49}$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.