Answer:
4. wavelength (λ)
5. slit distance (d)
Step-by-step explanation:
I assume you did a double-slit experiment? If so, then:
The number of bands observed on the screen depends on the wavelength (λ) and the slit distance (d), while the screen distance (L) does not directly affect the number of bands.
Wavelength (λ): The number of bands is directly proportional to the wavelength. When the wavelength increases, the fringe separation on the screen increases, resulting in a greater number of bands.
Slit distance (d): The number of bands is inversely proportional to the slit spacing (distance). When the slit spacing increases, the fringe separation on the screen decreases, resulting in a smaller number of bands.
Screen distance (L): The screen distance does not directly affect the number of bands. It primarily affects the size and overall pattern of the interference fringes but does not change the number of bands.
Summary:
Wavelength (λ) is directly proportional to the number of bands.
Slit distance (d) is inversely proportional to the number of bands.
Screen distance (L) does not directly affect the number of bands.