If yellow light emitted by a sodium lamp in Young's double-slit experiment is replaced by monochromatic blue light of the same intensity,then:

In $YDSE$ with two identical slits,when the upper slit is covered with a transparent sheet of mica,the second-order minima is observed above the center of the screen and the second-order maxima below it. Which of the following cannot be a possible value of the phase difference caused by the mica sheet?

An interference pattern was made by using red light. If the red light is replaced with blue light,the fringes will become

In Young's double slit experiment,the central bright fringe can be identified

In Young's double slit experiment,the $10^{th}$ order maximum is obtained at a point of observation in the interference pattern for a wavelength $\lambda_1 = 7000 \; \mathring{A}$. If the source is replaced by another one of wavelength $\lambda_2 = 5000 \; \mathring{A}$,what will be the order of the maximum at the same point (in $^{th}$)?

In a double slit experiment,at a certain point on the screen,the path difference between the two interfering waves is $\frac{1}{8}$ of a wavelength. The ratio of the intensity of light at that point to that at the centre of a bright fringe is: