Because frame of reference decides are your forces positive or negative. It is important for the direction of motion.
Answer:
540 nm
Explanation:
According to the question,
The refractive index of the soap bubble,
.
The thickness of the soap bubble wall is,
.
Now, for constructive interference of soap bubble.
.
Now for first order m=1.
Therfore,

Substitute all the variables in the above equation.
.
Therefore,
.
Therefore the visible light wavelength which is strongly reflected is 540 nm.
Here given that x is inversely depends of y
so as we increase the value of y so due to inverse dependency it will decrease the value of x
So here we can also say that when x inversely depends on y
so the product of x and y will remain constant here
so here the graph should be like this that if we increase the quantity on x axis then it will decrease the other quantity on y axis
<u><em>So here best appropriate graph must be option A</em></u>