Rankers Physics

Diffraction: Practice Problem & Solution

At the first minimum adjacent to the central maximum of a single-slit diffraction pattern the phase difference between the Huygens's wavelet from the edge of the slit and the wavelet from the mid point of the slit is: (2015 Re)
$\pi/8$
$\pi/4$
$\pi/2$
$\pi$

Solution Explained:

To solve this problem, we apply the core principles of Diffraction. Understanding the underlying formula is key to arriving at the correct answer below:

For the first minimum in single slit diffraction, the path difference between waves from opposite edges of the slit is $\lambda$, corresponding to a phase difference of $2\pi$. Between the edge and the midpoint, the path difference is $\lambda/2$, so the phase difference is $\pi$.

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