Directions : In the following question more than one of the answers given may be correct. Select the correct answer and mark it according to the code:
In the Young's double slit experiment, the interference pattern is found to have an intensity ratio between bright and dark fringes as 9. This implies that: (1) the intensities at the screen due to the two slits are 4 units and 1 unit respectively (2) the intensities at the screen due to two slits are 5 units and 4 units respectively (3) the amplitude ratio is 3 (4) the amplitude ratio is 2A) 1 and 2 are correct
B) 2 and 3 are correct
C) 1 and 4 are correct
D) 1, 2 and 3 are correct
Correct Answer: A
Solution :
\[\frac{{{I}_{\max }}}{{{I}_{\min }}}=\frac{{{(a+b)}^{2}}}{{{(a-b)}^{2}}}=9\] \[\therefore \] \[\frac{a+b}{a-b}=3\] Or \[a+b=3a-3b\] Or \[a=2b\] \[\therefore \] \[\frac{{{I}_{1}}}{{{I}_{2}}}=\frac{{{a}^{2}}}{{{b}^{2}}}=\frac{{{(2b)}^{2}}}{{{b}^{2}}}=4:1\]You need to login to perform this action.
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