Question

Part (a) In the simulation, choose the 'Slits' window. Select the Iasericon, dira choose the 'two slits' option. Click the 'screen' box, it may help to quantify the positions of the peaks by clicking 'Intensity'. Set the 'Slit Width' to the lowest setting (200 nm), and increase the light source amplitude to the maximum value. Set the barrier location to roughly half the distance between the light source and the screen. Finally, set the slit separation to 1750 nm. What happens in the simulation if you move from blue light to orange light? Choose 3 correct answers. The distance from the central maximum to the first fringe increases. The distance from the central maximum to the first fringe decreases. More fringes appear on the screen. Fewer fringes appear on the screen. The distance between bright fringes increases. The distance between bright fringes decreases. Part (b) Use the same initial set up as given in the previous question. Using violet light, what happens in the simulation if you increase the distance between two slits? Choose 3 correct answers. The distance from the central maximum to the first fringe increases. The distance from the central maximum to the first fringe decreases. More fringes appear on the screen. Fewer fringes appear on the screen. The distance between bright fringes increases. Part (c) Use the same initial set up as given in the previous question. Using violet light, what happens in the simulation if you move the two slits closer to the screen (i.e. decrease L by moving the barrier further to the right)? Choose 3 correct answers. The distance from the central maximum to the first fringe increases. The distance from the central maximum to the first fringe decreases. More fringes appear on the screen. Fewer fringes appear on the screen. The distance between bright fringes increases. The distance between bright fringes decreases.

Answer 1

In a double-slit experiment, moving from blue light to orange light increases the distance from the central maximum to the first fringe, results in fewer fringes on the screen, and increases the distance between bright fringes. Increasing slit separation with violet light increases the distance from the central maximum to the first fringe, the number of fringes, and the distance between bright fringes. Moving slits closer to the screen decreases the distance from the central maximum to the first fringe and the distance between fringes, but increases the number of observable fringes.

Step-by-step explanation:

The phenomenon in question here is double-slit diffraction, which refers to the interference pattern formed when light passes through two narrow slits. This experiment is a classic demonstration of the wave nature of light.

Part (a): When switching from blue light to orange light, the following three effects occur:

• The distance from the central maximum to the first fringe increases since orange light has a longer wavelength than blue light.
• Fewer fringes appear on the screen because the longer wavelength results in a less dense interference pattern.
• The distance between bright fringes increases for the same reason that more space is covered per fringe with the longer wavelength of orange light.

Part (b): When the distance between two slits using violet light is increased, these changes are observed:

• The distance from the central maximum to the first fringe increases, as the larger separation causes the fringes to be more spread out.
• More fringes appear on the screen because a greater separation allows more interference maxima to fit in the same space, given the same wavelength of light.
• The distance between bright fringes increases as the larger separation causes the interference pattern to spread out more.

Part (c): Moving the two slits closer to the screen results in:

• The distance from the central maximum to the first fringe decreases due to the reduction in the path difference between the two slits' light.
• More fringes appear on the screen since the overall interference pattern shrinks, allowing more fringes to fit into the same screen space.
• The distance between bright fringes decreases as the fringes are compressed closer together by moving the slits closer to the screen.