In $YDSE$,the separation between the slits is halved and the distance between the slits and the screen is doubled. The fringe width is

Two sources of light of wavelengths $2500 \text{ Å}$ and $3500 \text{ Å}$ are used in Young's double slit experiment simultaneously. Which orders of fringes of the two wavelength patterns coincide?

In Young's double-slit experiment,monochromatic light is used to illuminate two slits $A$ and $B$. Interference fringes are obtained on a screen in front of the slits. Now,if a thick glass plate is placed in the path of light from one of the slits,then:

Assertion: In Young's double slit experiment,if the wavelength of incident monochromatic light is doubled,the number of bright fringes on the screen will increase.
Reason: The maximum number of bright fringes on the screen is directly proportional to the wavelength of light used.

In Young's double slit experiment,the width of fringes can be increased if we decrease the

The distance between two coherent sources is $1 \ mm$. The screen is placed at a distance of $1 \ m$ from the sources. If the distance of the third bright fringe is $1.2 \ mm$ from the central fringe, the wavelength of light used is: