MCQ
Two coherent sources of intensities, $I_1$ and $I_2$ produce an interference pattern. The maximum intensity in the interference pattern will be
- A$I_1 + I_2$
- B$I_1^2 + I_2^2$
- C$(I_1 + I_2)^{2}$
- ✓${(\sqrt {{I_1}} + \sqrt {{I_2}} )^2}$
✓
Answer
Correct option: D.
${(\sqrt {{I_1}} + \sqrt {{I_2}} )^2}$
d
(d)Resultant intensity ${I_R} = {I_1} + {I_2} + 2\sqrt {{I_1}{I_2}} \,\cos \phi$
For maximum ${I_R},$ $\phi= {0^o}$
==> ${I_R} = {I_1} + {I_2} + 2\sqrt {{I_1}{I_2}} = {\left( {\sqrt {{I_1}} + \sqrt {{I_2}} } \right)^2}$
(d)Resultant intensity ${I_R} = {I_1} + {I_2} + 2\sqrt {{I_1}{I_2}} \,\cos \phi$
For maximum ${I_R},$ $\phi= {0^o}$
==> ${I_R} = {I_1} + {I_2} + 2\sqrt {{I_1}{I_2}} = {\left( {\sqrt {{I_1}} + \sqrt {{I_2}} } \right)^2}$
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