For a double-slit interference, what would happen to the distance between the bright fringes if you:

a) Decreased the distance between the slide and the screen
b) Increased the separation between the slits
c) Decreased the distance between the laser apparatus and the slide
d) Changed violet light to yellow light

To understand what would happen to the distance between the bright fringes in a double-slit interference experiment, let's break down your question into four parts and explain each scenario:

a) Decreased the distance between the slide and the screen:
In a double-slit interference experiment, when you decrease the distance between the slide (which contains the slits) and the screen (where the interference pattern is observed), the distance between the bright fringes would increase. This is because the fringe spacing is determined by the wavelength of the light and the distance between the slits. The closer the screen is to the slits, the larger the fringe spacing becomes.

b) Increased the separation between the slits:
If you increase the separation between the slits in the double-slit apparatus, the distance between the bright fringes would also increase. The fringe spacing is directly proportional to the slit separation. A larger separation between the slits would result in a broader pattern of interference fringes and hence a larger spacing between the bright fringes.

c) Decreased the distance between the laser apparatus and the slide:
Changing the distance between the laser apparatus and the slide (where the double slits are located) would not directly affect the distance between the bright fringes. The interference fringes depend on the distance between the slits and the screen, as well as the wavelength of the light, but they are not directly affected by the distance between the laser apparatus and the slide.

d) Changed violet light to yellow light:
When you change the color of the light used in a double-slit interference setup, such as from violet to yellow light, the distance between the bright fringes would remain the same. The color of light determines its wavelength, but it does not significantly affect the fringe spacing in this scenario. The fringe spacing is determined by the ratio of the wavelength of light to the distance between the slits. Therefore, changing the color of light without altering the other parameters would not affect the distance between the bright fringes.

In summary, the distance between the bright fringes in a double-slit interference experiment depends on the wavelength of light, the distance between the slits, and the distance between the screen and the slits. Changing the parameters like the distance between the slide and the screen or the separation between the slits will directly affect the fringe spacing, while other alterations such as the distance between the laser apparatus and the slide or the color of light used would have no or negligible impact.