In Young's double-slit experiment,the fringes are displaced by a distance $x$ when a glass plate of refractive index $1.5$ is introduced in the path of one of the beams. When this plate is replaced by another plate of the same thickness,the shift of fringes is $(3/2)x$. The refractive index of the second plate is

In Young's double-slit experiment,if the amplitudes of the interfering waves are not equal,then . . . . .

In Young's double slit arrangement, slits are separated by a gap of $0.5 \, mm$, and the screen is placed at a distance of $0.5 \, m$ from them. The distance between the first and the third bright fringe formed when the slits are illuminated by a monochromatic light of $5890 \, \text{Å}$ is

If the slit widths of $YDSE$ are in the ratio $1:4$,then the ratio of maximum to minimum intensity on the screen is: (in $:1$)

In Young's double slit experiment,the separation $d$ between the slits is $2 \ mm$,the wavelength $\lambda$ of the light used is $5896 \ \mathring{A}$,and the distance $D$ between the screen and slits is $100 \ cm$. It is found that the angular width of the fringes is $0.20^\circ$. To increase the fringe angular width to $0.21^\circ$ (with the same $\lambda$ and $D$),the separation between the slits needs to be changed to ...... $mm$.

When monochromatic light of wavelength $600 nm$ is used in Young's double slit experiment,the fifth order bright fringe is formed at $6 mm$ from the central bright fringe on the screen. If the experiment is conducted with light of wavelength $400 nm$,the third order bright fringe will be located at: (in $mm$)