$A$ ray of light from a monochromatic point source of light is incident at a point on the screen. If a thin mica film of thickness $t$ and refractive index $n$ is introduced in its path,then the optical path

Two point sources separated by $d = 5\, \mu m$ emit light of wavelength $\lambda = 2\, \mu m$ in phase. $A$ circular wire of radius $R = 20\, \mu m$ is placed around the sources as shown in the figure. Determine the nature of interference at points $A, B, C,$ and $D$.

Two monochromatic light waves of amplitudes $3A$ and $2A$ interfering at a point have a phase difference of $60^{\circ}$. The intensity at that point will be proportional to.......$A^2$

Two identical radiators have a separation of $d = \lambda /4$ where $\lambda$ is the wavelength of the waves emitted by either source. The initial phase difference between the sources is $\pi /4$. Then the intensity on the screen at a distant point situated at an angle $\theta = 30^\circ$ from the radiators is (here $I_o$ is the intensity at that point due to one radiator alone):

The path difference between two interference waves at a point on a screen is $11.5 \lambda$. The point is

The ratio of intensities of two waves producing interference is $9: 4$. The ratio of the resultant maximum and minimum intensities will be: