Constructive Interference

There is a destructive interference between the two waves of wavelength lambda coming from two different paths at a point. To get maximum sound or constructive interference at that point, the path of one wave is to be increased by

What is the minimum thickness of thin film required for constructive interference in the reflected light through it ? (Given, the refractive index of the film =1.5, wavelength of the lilght incident on the film =600 nm.

Two monochromatic and coherent point sources of light are placed at a certain distance from each other in the horizontal plane. The locus of all thos points in the horizontal plane which have constructive interference will be-

Two sound sources S_(1) and S_(2) emit pure sinussoidal waves in phase . If the speed of sound is 350 m//s , then (a) for what frequencies does constructive interference occur at point P ? (b) for what frequencies does destructive interference occur at point P ?

A radio transmitting station operating at a frequency of 120 MHz has two identical antennas that radiate in phase. Antenna B is 9 m to the right of antenna A. consider point P at a horizontal distance x to the right of antenna A as shown in figure. The value of x and order for which the constructive interference will occur at point P are