Question

Assertion (A) : No interfrence pattern is detected when two coherent sources are very closer to each other. (i.e separation almost zero)

Reason (R ) : The fringe width is inversely proportional to the distance between the two slits

(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c) If assertion is true but reason is false.
(d) If assertion and reason both are false.

Answer 1

Interference patterns can still be observed when two coherent light sources, such as slits, are very close to each other, and while fringe width is inversely proportional to slit distance, the assertion is false.

Step-by-step explanation:

The assertion about interference patterns not being detected when two coherent sources are very close together is false. Even when two coherent sources of light, such as the slits in a double-slit experiment, are close to each other, interference fringes can be observed. The reason given, stating that the fringe width is inversely proportional to the distance between the slits, is true, but it is not the correct explanation for the assertion given.

Interference patterns arise due to the superposition of two sets of waves emanating from the slits, leading to regions of constructive and destructive interference on the screen. The fringe width is indeed related to the distance between the slits and the wavelength of the light used; however, the assertion that no interference pattern is detected with almost zero separation is incorrect. An interference pattern can still be observed even if the slits are very close together, and the fringe width would be very large.