Let us start from considering monochromatic light as an incidence on the film of a thickness t whose material has an index of refraction n determined by their respective properties.
From this point of view part of the light will be reflated and the other will be transmitted to the thin film. That additional distance traveled by the ray that was reflected from the bottom will be twice the thickness of the thin film at the point where the light strikes. Therefore, this relation of phase differences and additional distance can be expressed mathematically as

We are given the second smallest nonzero thickness at which destructive interference occurs.
This corresponds to, m = 2, therefore


The index of refraction of soap is given, then

Combining the results of all steps we get

Rearranging, we find



<em>A statement that is true for ALL of the examples of electromagnetic waves is that;</em>
A) They all move at the same speed in a vacuum
<u>The reason for qualifying 'in vacuum' is because EM waves of different frequencies often propagate at different speeds through material. Generally speaking, we say that light travels in waves, and all electromagnetic radiation travels at the same speed which is about 3.0 * 108 meters per second through a vacuum.</u>
<span>A major characteristic of both volcanoes and earthquakes is that they are located in the same geographic area. Most earthquakes are along the edges of tectonic plates. This is where most volcanoes are too. Most earthquakes directly beneath a volcano are caused by the movement of magma.</span>
Assuming motion is on a straight path, the result of two positive components of a vector would also be a positive value since both are having positive signs and directions. The direction would be the same with the motion as well. Hope this answers the question. Have a nice day.