Single/double slit diffraction intensity

[EF17xx]

Homework Statement

SINGLE SLIT
Why does the intensity at maxima decrease further away from the central maxima in a single slit diffraction.

DOUBLE SLIT
Slit width:
Why is the intensity of a double slit interference pattern the same at each maxima. (constructive interference)
When the slit width is negligible

BUT NOT
when the slit width is not negligible.

2. Homework Equations
λ/b=sinθ
Intensity propoportional to Amplitude^2

The Attempt at a Solution

Could someone please explain using simple vocabulary/ terminology and examples/analogies as I sometimes get confused by very experienced physicists who assume I know what they're talking about. :) :)

 

[EF17xx]

Would also like to know why when slit separation is SMALLER the maxima are further apart.
I understand this is the case when simply looking at the formula. s=λD/d but could someone please put this into words for why it is like that.

 

[drvrm]

Homework Statement

SINGLE SLIT
Why does the intensity at maxima decrease further away from the central maxima in a single slit diffraction.

The Attempt at a Solution

Could someone please explain using simple vocabulary/ terminology and examples/analogies as I sometimes get confused by very experienced physicists who assume I know what they're talking about. :) :)

the single slit diffraction pattern and intensity distribution is a lab experiment and the intensity one observes is due to interference of diffracted rays. if you wish to understand it in detail
see
https://phys.libretexts.org/TextMap...ion/4.2:_Intensity_in_Single-Slit_Diffraction
and then proceed further.

 

[drvrm]

for double slit a similar text explaining the intensity pattern is there
pl.see
https://phys.libretexts.org/TextMap...)/4:_Diffraction/4.3:_Double-Slit_Diffraction