Question

Light of wavelength 500 nm is incident on a narrow slit of width 150 nm. Which model of light most accurately predicts the behavior of the light after it passes through the slit? Explain your answer.

Final Answer

The wave nature of light model predicts the diffraction pattern that would be seen since the slit width is less than $\lambda$.

### Solution video

# OpenStax College Physics for AP® Courses, Chapter 25, Problem 2 (Test Prep for AP® Courses)

vote with a rating of
votes with an average rating of
.

Video Transcript

This is College Physics Answers with Shaun Dychko. Light with a wavelength of 500 nanometers is incident on a narrow slit with a width of only 150 nanometers and the question is which model of light most accurately predicts the behavior of the light after it passes through the slit? So the answer is the wave nature of light predicts this behavior because we'll see this diffraction pattern we'll see a large maximum intensity directly in line with the slit and then to the side of this central maximum will have minima and maxima and then alternating minima, maxima, minima, maxima and the only way to explain this variable intensity with distance from the central maximum is with the wave nature of light. So well, the slid width is this capital

*D*here's a formula that tells us where this destructive minima will be and*D*is the slit width,*λ*is the wavelength and*m*is the order of the minima and it can be some natural number 1, 2, 3, 4 and on and this angle*Θ*is the angle between this horizontal, central axis and the minimum here so this would be*Θ*1, 2, 3... this will be*Θ*4... the third minimum. Okay!