In YDSE set up (see fig.), the light sources executes SHM between P and Q according to the equation `x = A sin omega t`, S being the mean position. Assume `d rarr 0` and `A lt lt L`. `omega` is small enough to neglect Doppler effect. If the sources were stationary at S, intenstiy at O would be `I_(0)`
Read the paragraph carefully and answer the following questions.

The fractional change in intensity of the central maximum as function of time is

Options

A. `(A sin omega t)/(L)`
B. `(2 A sin omega t)/(L)`
C. `(3 A sin omega t)/(L)`
D. `(4 A sin omega t)/(L)`

Answer

b

Explanation

`I prop (1)/(("distance")^(2))`
`:. (Delta I)/(I_(0)) = (l_(2) - (L - x)^(2))/(L^(2)) ~~ (2 A sin omega t)/(L)`